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Drug Abuse Warning Network, 2011:
National Estimates of Drug-Related
Emergency Department Visits



U.S. DEPARTMENT OF HEALTH AND HUMAN SERVICES
Substance Abuse and Mental Health Services Administration
Center for Behavioral Health Statistics and Quality



ACKNOWLEDGMENTS

This report was prepared for the Substance Abuse and Mental Health Services Administration (SAMHSA) by RTI International (a trade name of Research Triangle Institute, Research Triangle Park, NC) under contract number HHSP23320095651WC, with SAMHSA, U.S. Department of Health and Human Services (HHS). Rong Cai served as the Government Project Officer.

PUBLIC DOMAIN NOTICE

All material appearing in this publication is in the public domain and may be reproduced or copied without permission from SAMHSA. Citation of the source is appreciated. However, this publication may not be reproduced or distributed for a fee without the specific, written authorization of the Office of Communications, SAMHSA, HHS.

RECOMMENDED CITATION

Substance Abuse and Mental Health Services Administration, Drug Abuse Warning Network, 2011: National Estimates of Drug-Related Emergency Department Visits. HHS Publication No. (SMA) 13-4760, DAWN Series D-39. Rockville, MD: Substance Abuse and Mental Health Services Administration, 2013.

ELECTRONIC ACCESS

This publication may be downloaded from http://store.samhsa.gov. Or please call SAMHSA at

1-877-SAMHSA-7 (1-877-726-4727)
(English and Español).

ORIGINATING OFFICE

Center for Behavioral Health Statistics and Quality
Substance Abuse and Mental Health Services Administration
1 Choke Cherry Road, Rockville, MD 20857

May 2013



CONTENTS

Highlights
All Drug-Related ED Visits
Overall Drug Misuse or Abuse
Illicit Drugs
Nonmedical Use of Pharmaceuticals
Drugs and Alcohol Taken Together
Underage Drinking
Drug-Related Suicide Attempts
Seeking Detox Services
Adverse Reactions to Pharmaceuticals
Accidental Ingestion of Drugs

1. Introduction
1.1 Major Features of DAWN
1.1.1 What Is a DAWN Case?
1.1.2 What Drugs Are Included in DAWN?
1.1.3 What Is Covered in This Publication?
1.2 Hospital Participation in 2011
1.3 Estimates of ED Visits
1.4 Rates of ED Visits per 100,000 Population
1.5 Sampling Error
1.6 Suppression
1.7 Comparisons Across Years
1.8 Limitations of the Data

2. Overall Drug Misuse or Abuse
2.1 ED Visits Involving Overall Drug Misuse or Abuse, 2011
2.2 Trends in ED Visits Involving Drug Misuse or Abuse, 2004–2011

3. Illicit Drugs
3.1 ED Visits Involving Illicit Drugs, 2011
3.2 Trends in ED Visits Involving Illicit Drugs, 2004–2011

4. Alcohol
4.1 ED Visits Involving Drugs and Alcohol Taken Together, 2011
4.2 Underage Drinking
4.3 Trends in ED Visits Involving Alcohol, 2004–2011

5. Nonmedical Use of Pharmaceuticals
5.1 ED Visits Involving Nonmedical Use of Pharmaceuticals, 2011
5.2 Trends in ED Visits Involving Nonmedical Use of Pharmaceuticals, 2004–2011

6. Drug-Related Suicide Attempts
6.1 ED Visits Involving Drug-Related Suicide Attempts, 2011
6.2 Trends in ED Visits Involving Drug-Related Suicide Attempts, 2004–2011

7. Seeking Detox Services
7.1 ED Visits Involving Seeking Detox Services, 2011
7.2 Trends in ED Visits Involving Seeking Detox Services, 2004–2011

8. Adverse Reactions To Pharmaceuticals
8.1 ED Visits Involving Adverse Reactions to Pharmaceuticals, 2011
8.2 Trends in ED Visits Involving Adverse Reaction to Pharmaceuticals, 2005–2011

9. Accidental Ingestion of Drugs
9.1 ED Visits Involving Accidental Ingestion of Drugs, 2011
9.2 Trends in ED Visits Involving Accidental Ingestion of Drugs by Patients Aged 5 and Under, 2004–2011

List of Tables

Table 1. DAWN analytic groups
Table 2. ED visits involving drug misuse or abuse, by drug combinations, 2011
Table 3. Trends in ED visits involving drug misuse or abuse, by drug combinations, 2004–2011
Table 4. ED visits involving illicit drugs, 2011
Table 5. Rates of ED visits per 100,000 population involving illicit drugs, 2011
Table 6. ED visits involving illicit drugs, by patient demographics, 2011
Table 7. Rates of ED visits per 100,000 population involving illicit drugs, by patient demographics, 2011
Table 8. ED visits and rates involving illicit drugs, by patient disposition, 2011
Table 9. Trends in ED visits involving illicit drugs, by selected drugs, 2004–2011
Table 10. ED visits involving alcohol, 2011
Table 11. ED visits involving drugs and alcohol taken together, 2011
Table 12. ED visits involving alcohol, by drug, 2011
Table 13. ED visits involving drugs and alcohol taken together, by patient demographics, 2011
Table 14. ED visits involving drugs and alcohol taken together, by patient disposition, 2011
Table 15. ED visits involving underage drinking, 2011
Table 16. ED visits involving alcohol, by patients aged 12 to 17 and 18 to 20, 2011
Table 17. Trends in ED visits involving alcohol, 2004–2011
Table 18. ED visits involving nonmedical use of pharmaceuticals, by selected drugs, 2011
Table 19. ED visits and rates involving nonmedical use of pharmaceuticals, by patient demographics, 2011
Table 20. ED visits and rates involving nonmedical use of pharmaceuticals, by patient disposition, 2011
Table 21. Trends in ED visits involving nonmedical use of pharmaceuticals, by selected drugs, 2004–2011
Table 22. ED visits involving drug-related suicide attempts, by selected drugs, 2011
Table 23. ED visits involving drug-related suicide attempts, by patient demographics, 2011
Table 24. ED visits involving drug-related suicide attempts, by patient disposition, 2011
Table 25. Trends in ED visits for drug-related suicide attempts, by selected drugs, 2004–2011
Table 26. ED visits involving seeking detox services, by selected drugs, 2011
Table 27. ED visits involving seeking detox services, by patient demographics, 2011
Table 28. ED visits involving seeking detox services, by patient disposition, 2011
Table 29. Trends in ED visits involving seeking detox services, by selected drugs, 2004–2011
Table 30. ED visits involving adverse reaction to pharmaceuticals, 2011
Table 31. ED visits and rates involving adverse reaction to pharmaceuticals, by patient demographics, 2011
Table 32. ED visits and rates involving adverse reaction to pharmaceuticals, by patient disposition, 2011
Table 33. Trends in ED visits involving adverse reaction to pharmaceuticals, by selected drugs, 2005–2011
Table 34. ED visits involving accidental ingestion of drugs by patients aged 5 and under, 2011
Table 35. ED visits and rates involving accidental ingestion of drugs by patients aged 5 and under, by patient demographics, 2011
Table 36. ED visits and rates involving accidental ingestion of drugs by patients aged 5 and under, by patient disposition, 2011
Table 37. Trends in ED visits involving accidental ingestion of drugs by patients aged 5 and under, by selected drugs, 2004–2011

List of Figures

Figure 1. Rates of drug-related ED visits per 100,000 population, by age group, 2011
Figure 2. Rates of ED visits per 100,000 population involving illicit drugs, 2011
Figure 3. Rates of ED visits per 100,000 population involving illicit drugs, by selected drugs, age, and sex, 2011
Figure 4. Rates of ED visits per 100,000 population involving drugs and alcohol, by age and sex, 2011
Figure 5. Rates of ED visits per 100,000 population involving alcohol, by patients aged 12 to 17 and 18 to 20, 2011
Figure 6. Rates of ED visits per 100,000 population involving nonmedical use of pharmaceuticals, by age and sex, 2011
Figure 7. Rates of ED visits per 100,000 population involving drug-related suicide attempts, by age and sex, 2011
Figure 8. Rates of ED visits per 100,000 population involving seeking detox services, by age and sex, 2011
Figure 9. Rates of ED visits per 100,000 population involving adverse reaction to pharmaceuticals, by age and sex, 2011
Figure 10. Rates of ED visits per 100,000 population involving accidental ingestion of pharmaceuticals, by age, 2011

List of Attachments

Attachment A. Glossary of DAWN Terms, 2011 Update
Attachment B. Drug Abuse Warning Network Methodology Report, 2011 Update
Attachment C. Guide to Drug Abuse Warning Network Trend Tables, 2011 Update

HIGHLIGHTS

This publication presents national estimates of drug-related visits to hospital emergency departments (EDs) for the calendar year 2011, based on data from the Drug Abuse Warning Network (DAWN). Also presented are comparisons of 2011 estimates with those for 2004, 2009, and 2010. DAWN is a public health surveillance system that monitors drug-related ED visits for the Nation and for selected metropolitan areas. The Substance Abuse and Mental Health Services Administration (SAMHSA), U.S. Department of Health and Human Services (HHS), is the agency responsible for DAWN. SAMHSA is required to collect data on drug-related ED visits under Section 505 of the Public Health Service Act.

DAWN relies on a nationally representative sample of general, non-Federal hospitals operating 24-hour EDs, with oversampling of hospitals in selected metropolitan areas. In each participating hospital, ED medical records are reviewed retrospectively to find the ED visits that involved recent drug use. All types of drugs—illegal drugs, prescription drugs, over-the-counter pharmaceuticals (e.g., dietary supplements, cough medicine), and substances inhaled for their psychoactive effects—are included. Alcohol is considered an illicit drug when consumed by patients aged 20 or younger. For patients aged 21 or older, though, alcohol is reported only when it is used in conjunction with other drugs.

Marked findings of this report are (a) a 29 percent increase in the number of drug-related ED visits involving illicit drugs in the short term between 2009 and 2011; (b) simultaneous, short-term increases in the involvement of both illicit and licit stimulant-like drugs; and (c) some indications that the pace of increases in pharmaceutical involvement is slowing down.

All Drug-Related ED Visits

In 2011, over 125 million visits were made to EDs in general-purpose, non-Federal hospitals operating 24-hour EDs in the United States. DAWN estimates that over 5 million of these visits, or about 1,626 ED visits per 100,000 population, were related to drugs, a 100 percent increase since 2004. In 2011, drug-related visits range from a low of 288 visits per 100,000 population aged 6 to 11 to a high of 2,477 visits per 100,000 population aged 18 to 20 (Figure 1).

Figure 1. Rates of drug-related ED visits per 100,000 population, by age group, 2011

Figure 1     D

SOURCE: Center for Behavioral Health Statistics and Quality, SAMHSA, Drug Abuse Warning Network, 2011.

Overall Drug Misuse or Abuse

In 2011, DAWN estimates that about 2.5 million ED visits resulted from medical emergencies involving drug misuse or abuse, the equivalent of 790 ED visits per 100,000 population. For those aged 20 or younger, the rate is 500 visits; for those aged 21 or older, the rate is 903 visits.

Understanding that a visit may appear in more than one group, DAWN found that, out of all drug misuse or abuse ED visits,

In the long term, between 2004 and 2011, the annual overall number of ED visits attributable to drug misuse or abuse has risen steadily each year for a total increase of 52 percent, or about 844,000 visits. In the short term, between 2009 and 2011, ED visits involving overall misuse or abuse increased by 19 percent, or by about 400,000 visits over the 2 years. Almost half of the net increase in visits seen in the 8 years from 2004 to 2011 occurred in the last 2 years of the period, 2009 to 2011. Unlike the long-term trends, though, which are largely driven by rises in pharmaceutical involvement, the short-term rise reflects the 38 percent increase seen in ED visits involving illicit drugs only, with no significant increases over the last 2 years for visits involving pharmaceuticals or alcohol alone or combinations of pharmaceuticals, alcohol, and illicit drugs.

Illicit Drugs

Of the approximately 2.5 million drug misuse or abuse ED visits that occurred during 2011, a total of 1,252,500, or just over half (51%), involved illicit drugs. That is the equivalent of 402 ED visits for each 100,000 persons in the U.S. population. The highest rates of involvement were found for cocaine and marijuana (162 and 146 ED visits per 100,000 population, respectively). Almost 40 percent of visits involving illicit drugs resulted in some form of follow-up, including admission to the hospital (24%), transfer to another health care facility (10%), or referral to a drug detox/dependency program (6%). The overall level of ED visits involving illicit drugs was stable in the long term, between 2004 and 2011. In the short term, between 2009 and 2011, though, visits involving illicit drugs have experienced a 29 percent increase.

Nonmedical Use of Pharmaceuticals

DAWN estimates that over 1.2 million ED visits involved nonmedical use of prescription medicines, over-the-counter drugs, or other types of pharmaceuticals in 2011. At 46 percent, pain relievers were the most common type of drugs involved in medical emergencies associated with nonmedical use of pharmaceuticals; narcotic pain relievers were involved in 29 percent. Some form of follow-up was observed for almost 40 percent of visits. Overall, medical emergencies related to nonmedical use of pharmaceuticals increased 132 percent in the period from 2004 to 2011, with opiate/opioid involvement rising 183 percent. In the short term, between 2009 and 2011, overall pharmaceutical involvement increased just 15 percent, and opiate/opioid involvement saw no significant increase. One category of drugs that has experienced both short- and long-term increases in involvement is central nervous system (CNS) stimulants (e.g., ADHD drugs). The short-term increase in involvement of CNS stimulants (85%) echoes a similar short-term rise observed for involvement of illicit stimulants (amphetamines/methamphetamine) (71%).

Drugs and Alcohol Taken Together

In 2011, about a quarter of all ED visits associated with drug misuse or abuse also involved alcohol. Among all visits involving alcohol, 58 percent involved illicit drugs and 56 percent involved pharmaceuticals. Among all visits involving illicit drugs, about 30 percent also involved alcohol; higher levels of alcohol involvement were found for visits involving ketamine (72%). Among all visits involving pharmaceuticals, 25 percent also involved alcohol. Alcohol was present in 38.6 percent of visits involving penicillin, 38 percent of visits involving CNS stimulants, and 31 percent of visits involving antidepressants. Just under half of the patients received follow-up care.

Underage Drinking

In 2011, of the nearly 440,000 drug abuse–related ED visits made by patients aged 20 or younger, more than 40 percent involved alcohol. The rate of medical emergencies involving alcohol was 287 visits per 100,000 population aged 12 to 17 and 858 per 100,000 population aged 18 to 20, almost a threefold difference. Visits involving drugs and alcohol have remained stable over the period from 2004 through 2011, with no short-term increases.

Drug-Related Suicide Attempts

DAWN estimated there were over 200,000 ED visits resulting from drug-related suicide attempts in 2011. Almost all involved a prescription drug or over-the-counter medication. Over 80 percent of patients attempting drug-related suicide had some form of follow-up after their ED visit. The number of drug-related suicide attempts has risen 41 percent from 2004 to 2011.

Seeking Detox Services

DAWN estimates that there were about a quarter million drug-related ED visits for patients seeking detox or substance abuse treatment services during 2011. Nearly 60 percent of ED patients classified as seeking detox obtained some follow-up based on their ED visit: about 30 percent were admitted to the hospital, 20 percent were referred to detox/treatment services, and 7 percent were transferred to another facility. While the overall number of ED visits by patients seeking detox for illicit drugs did not change significantly either in the long or short term, a short-term increase of 36 percent between 2009 and 2011 was observed for patients seeking detox from heroin; there were over 20,000 more visits in 2011 than in 2009.

Adverse Reactions to Pharmaceuticals

For 2011, DAWN estimates that over 2.3 million ED visits, or 738 visits per 100,000 population, involved adverse reactions to prescription medicines, over-the-counter drugs, or other types of therapeutic substances. Rates for women were higher than for men (887 and 584 visits per 100,000 population, respectively). For children aged 5 and under, the rate of ED visits for adverse reactions was 842 visits per 100,000 population. The rate dropped to a low of 248 visits for children aged 6 to 11 and then rose consistently to reach a high of 1,526 visits for patients aged 65 or older. About three quarters of patients were treated and released, and about a fifth of patients were admitted to the hospital. ED visits resulting from adverse reactions to pharmaceuticals increased 84 percent in the long term, rising from about 1.3 million visits in 2005 to about 2.3 million visits in 2011. The number of ED visits for adverse reactions to pharmaceuticals rose by about a quarter million visits (or more) per year between 2005 and 2008, leveling off at about 2.3 million visits per year over the period from 2009 to 2011.

Accidental Ingestion of Drugs

The preponderance of ED visits for accidental ingestion involved children aged 5 and under. In 2011, out of a total of 113,634 visits, over 77,000 involved children in this age range. The rate of visits for accidental drug ingestion was about 25 times higher for children aged 5 and under than for adults: 318 visits per 100,000 children aged 5 and under compared with 13 visits per 100,000 population for the general adult population aged 21 or older. Pain relievers were the most common class of drugs involved in accidental ingestion among children aged 5 and under, appearing in 25 percent of visits. Medical emergencies related to accidental ingestions by patients aged 5 and under were stable from 2004 to 2011, though increases were observed for particular drug groups. With over 8,000 visits recorded in 2011, ED visits involving drugs to treat anxiety and insomnia rose 120 percent since 2004. With about 5,000 visits in 2011, visits involving narcotic pain relievers increased 225 percent over that period.

1. INTRODUCTION

This publication presents estimates of drug-related emergency department (ED) visits from the Drug Abuse Warning Network (DAWN) for 2011, with comparison of estimates for 2004, 2009, and 2010. DAWN is a public health surveillance system that monitors patients' medical records of ED visits for the Nation to identify those visits that are related to drug use, misuse, and abuse. The Center for Behavioral Health Statistics and Quality (CBHSQ) of the Substance Abuse and Mental Health Services Administration (SAMHSA), U.S. Department of Health and Human Services (HHS), has been responsible for DAWN operations since 1992.

This introduction provides a brief description of the major features of DAWN and the statistics presented in this report. Survey findings, as well as comparisons to earlier years' data, are organized in eight sections, with each section focusing on a specific type of ED visit (as listed in Table 1). Additional details on DAWN terminology and methodology are provided as attachments to this document. Detailed tables of DAWN estimates, this document, its attachments, other reports using DAWN data, and other methodology reports are available at the DAWN Web site.1 As they become available, DAWN data are accessible through SAMHSA's Data Archive (SAMHDA).2

Table 1. DAWN analytic groups
Analytic group Description
All Visits This group includes all visits that are reportable to DAWN without regard for the reason for the visit or the specific drugs involved. It includes visits involving all forms of drug misuse or abuse plus visits resulting from adverse reaction, accidental ingestion, suicide attempts, and visits where patients were seeking detoxification services. These estimates are useful for looking at overall levels of drug involvement in ED visits.
Drug-related ED visits that involve drug misuse or abuse
All Misuse and Abuse This analytic category includes ED visits that involve all forms of drug misuse or abuse, as defined by DAWN. This category is the combination of visits from the following four analytic groups: illicit drug visits, nonmedical use of pharmaceuticals, alcohol-related visits, and underage drinking. A visit may appear in more than one of those subgroups, but it will appear only once in this overall group. Suicide attempt visits and seeking detox visits will be included in this category if illicit drugs were involved.
Illicits (excluding alcohol) This analytic category includes ED visits that involve the use of drugs that have limited or no therapeutic value and are generally illegal if taken without a prescription. These substances include cocaine, heroin, marijuana, synthetic cannabinoids, amphetamines, methamphetamine, MDMA (Ecstasy), GHB (gamma-Hydroxybutyric acid), flunitrazepam (Rohypnol®), ketamine, LSD, PCP, and hallucinogens. Visits involving the inhalation of substances for their psychoactive properties (e.g., sniffing model airplane glue) are included.
Nonmedical Use of Pharmaceuticals This analytic category includes ED visits that involve nonmedical use of pharmaceuticals: patients who took a higher than prescribed or recommended dose of their own medication, patients who took a pharmaceutical prescribed for another person, malicious poisoning of the patient by another individual, and documented substance abuse involving pharmaceuticals.
All Alcohol This analytic category includes ED visits involving alcohol. For adults aged 21 and older, the alcohol was found in combination with other drugs. For patients under the age of 21, the visit may involve alcohol alone or in combination with other drugs.
Underage Drinking This analytic category includes ED visits that involve alcohol use (alone or with other drugs) for patients under the age of 21. Underage drinking is an important barometer of adolescent drinking patterns and a predictor of more serious substance abuse problems in young adults.
Suicide Attempts This analytic category includes ED visits that involve drug-related suicide attempts. It includes visits for drug overdoses and for suicide attempts by other means (e.g., using a firearm) if drugs were involved or related to the suicide attempt. Inclusion in this analytic category has no restrictions on the type of drug used.
Seeking Detox This analytic category includes nonemergency requests made through the ED for admission to detoxification unit, visits to obtain medical clearance before being incarcerated, and acute emergencies where an individual is experiencing withdrawal symptoms and requests detox. These estimates do not include patients who seek or enter the hospital's detox unit through other avenues.
Drug-related ED visits that do NOT involve drug misuse or abuse
Adverse Reactions This analytic category includes ED visits in which an adverse health consequence (e.g., side effects or an allergic reaction) resulted when taking prescription drugs, over-the-counter medications, or dietary supplements as prescribed or recommended.
Accidental Ingestions This analytic category includes ED visits in which an individual accidentally or unknowingly used or was administered a prescription drug, over-the-counter medication, or dietary supplement. Drug-related accidental ingestions typically involve patients aged 5 and under.

1.1 Major Features of DAWN

1.1.1 What Is a DAWN Case?

A DAWN case is any ED visit involving recent drug use that is implicated in the ED visit. The reason a patient used a drug is not part of the criteria for considering a visit to be drug related. Therefore, DAWN includes ED visits resulting from accidental ingestions and adverse reactions as well as explicit drug abuse.

1.1.2 What Drugs Are Included in DAWN?

DAWN captures drugs that are explicitly named in the medical record as being involved in the ED visit. The relationship between the ED visit and the drug use need not be causal. That is, an implicated drug may or may not have directly caused the condition generating the ED visit; the ED staff simply named it as being involved. Conversely, DAWN does not report medications or pharmaceuticals that the ED medical records mention as having been taken by the patient but that are unrelated to the ED visit.

Within those guidelines, DAWN collects data on all types of drugs, including the following:

1.1.3 What Is Covered in This Publication?

This report provides detailed information on ED visits involving drug use, misuse, or abuse for the years 2004 through 2011. The types of ED visits (referred to as analytic groups) highlighted in this publication are listed in Table 1. The analytic groups are defined by the reason for the visit and the types of drugs involved. Because a visit may involve multiple types of drugs (e.g., an illicit drug, such as marijuana, and a pharmaceutical, such as hydrocodone), a single visit may appear in multiple analytic groups.

1.2 Hospital Participation in 2011

DAWN relies on a nationally representative sample of hospitals with oversampling of hospitals in selected metropolitan areas. The universe of hospitals eligible for DAWN includes non-Federal, short-stay, general medical and surgical facilities in the United States that operate 24-hour EDs. DAWN excludes specialty hospitals (e.g., pediatric hospitals), long-term care facilities, and Federal facilities (e.g., Veterans Health Administration hospitals). The American Hospital Association Annual Survey Database (ASDB) was used to identify the original frame members. Subsequent ASDB surveys are used annually to identify "births" of new hospitals that open and "deaths" of hospitals that close or merge with other hospitals.

For 2011, 5.2 million charts out of a universe of 12.2 million charts were reviewed to determine if a visit was drug related. Data on 229,211 drug-related ED visits submitted by 233 hospitals were used for estimation. The overall visit weighted response rate was 35.2 percent.

1.3 Estimates of ED Visits

This publication reports nationally representative estimates of drug-related ED visits for the United States. Estimates are calculated by applying weights and adjustments to the data provided by the sampled hospitals participating in DAWN. The primary sampling weights reflect the probability of hospital selection, and separate adjustment factors are included to account for sampling of ED visits, nonresponse, data quality, and the known total of ED visits delivered by the universe of eligible hospitals, as reported by the most current ASDB survey.

Many of the tables in this report provide estimates of visits, by drug. DAWN is able to identify more than 3,300 individual drugs (which map to more than 19,000 individual brands and street names).3 The more commonly involved drugs and drug categories were selected for inclusion in the drug detail tables appearing in this report. Because (a) a single ED visit may involve multiple drugs, or (b) the same drug may be reported both under its specific drug name and under its drug category, the sum of ED visits from different rows in the drug detail tables will be greater than the total number of visits. For the same reason, percentages will add to more than 100.

1.4 Rates of ED Visits per 100,000 Population

Standardized measures are helpful when comparing levels of drug-related ED visits for different age and sex groups. This publication reports rates of ED visits per 100,000 population by age groups and sex groups per year, e.g., visits per 100,000 population aged 12 to 17 or visits per 100,000 male population. Population estimates are based on counts provided by the U.S. Census Bureau.4 Population-based rates for race/ethnicity categories are not reported because race/ethnicity information is often missing from ED records; a dash (—) is displayed instead.

1.5 Sampling Error

Because DAWN relies on a sample of hospitals, each estimate produced from the DAWN ED data is subject to sampling variability, the variation in estimates that would be observed naturally if different samples were drawn from the same population using the same procedures. One measure of sampling variability of an estimate used in this publication is the relative standard error (RSE). The precision of an estimate is inversely related to its RSE. That is, the greater the RSE, the lower the precision. A second measure of sampling error used in this publication is the 95 percent confidence interval (CI). A 95 percent CI means that if repeated samples were drawn from the same population of hospitals using the same sampling and data collection procedures, the true population value would fall within the CI 95 percent of the time. A CI, which is expressed as a range of values, is useful because the interval reflects both the estimate and its particular margin of error. For example, in 2011, there were 2,462,948 ED visits associated with drug misuse or abuse with a CI of 2,112,868 to 2,813,028. The CI indicates with a high degree of confidence that the actual number was within this range.

1.6 Suppression

An asterisk (*) is displayed in the place of suppressed estimates and rates. Data may be suppressed to protect patient confidentiality or to ensure that published findings meet statistical standards of reliability for survey results. In all DAWN published materials, estimates are suppressed according to the following rules:

Ratios (percentages or rates per 100,000 population) based on suppressed estimates are likewise suppressed.

1.7 Comparisons Across Years

In this publication, between-year changes are assessed by comparing estimates for 2011 with those for 2004, 2009, and 2010.5 This publication reports only those between-year changes that are statistically significant at the p < 0.05 level. The p-value is a measure of the probability (p) that the difference between two estimates could have occurred by chance, if the estimates being compared were really the same. The larger the p-value, the more likely the difference could have occurred by chance. For example, if the difference between two DAWN estimates has a p-value of 0.01, it means that there is a 1 percent probability that the difference observed could be due to chance alone.

The redesign of DAWN in 2003 altered most of DAWN's core features. Changes were made to the design of the hospital sample, the protocol for selecting charts to review, the eligibility criteria for being a DAWN case, and the data items submitted on these cases. These changes created a permanent disruption in trends. As a result, comparisons cannot be made between old DAWN (2003 and prior years) and the redesigned DAWN (2004 and forward).

1.8 Limitations of the Data

Readers are advised to consider the following limitations to the DAWN data when interpreting results:

2. OVERALL DRUG MISUSE OR ABUSE

2.1 ED Visits Involving Overall Drug Misuse or Abuse, 2011

For 2011, DAWN estimates that there were over 5.1 million drug-related ED visits. Of these, 2.5 million ED visits were associated with drug misuse or abuse (Table 2). That is the equivalent of 790.4 ED visits for each 100,000 persons in the Nation; for those aged 20 or younger, the rate is 500.0 visits; for those aged 21 or older, the rate is 903.4 visits.

Table 2. ED visits involving drug misuse or abuse, by drug combinations, 2011
Drug combinations (1) ED visits Percent of
ED visits
RSE (%) 95% CI:
Lower
bound
95% CI:
Upper
bound
(1) The classification of drugs used in DAWN is derived from the Multum Lexicon, © 2012 Lexi-Comp, Inc. and/or Cerner Multum, Inc. The classification was modified to meet DAWN's unique requirements (2011). The Multum Licensing Agreement governing use of the Lexicon can be found on the DAWN Web site at http://www.samhsa.gov/data/dawn/MultumLicenseAgreement.pdf.
(2) Estimates of ED visits are based on a representative sample of general, non-Federal, short-stay hospitals in the United States with 24-hour EDs.
(3) ED patients aged 21 or older for whom alcohol was the only drug associated with their ED visits are not considered DAWN cases.
(4) When present with other drugs, alcohol is reportable for patients of all ages.
NOTE: CI = confidence interval. RSE = relative standard error. A dash (—) indicates a blank cell.
SOURCE: Center for Behavioral Health Statistics and Quality, SAMHSA, Drug Abuse Warning Network, 2011.
Total ED visits, drug misuse or abuse (2) 2,462,948 100.0 7.30 2,112,868 2,813,028
Illicit drug(s) only    656,025   26.6 12.7    493,149    818,902
Alcohol only (age < 21) (3)    117,653     4.8 10.6      93,260    142,047
Pharmaceutical(s) only    835,275   33.9   6.4    730,440    940,110
Combinations            —     —    —            —            —
Illicit drug(s) with alcohol (4)    261,125   10.6 13.7    191,207    331,042
Illicit drug(s) with pharmaceutical(s)    247,342   10.0 17.3    163,707    330,976
Alcohol with pharmaceutical(s)    257,520   10.5   7.4    220,030    295,010
Illicit drug(s) with alcohol and pharmaceutical(s)      88,008     3.6 15.5      61,209    114,808

Of the ED visits in 2011 that involved drug misuse or abuse, nearly two thirds (64.9%) were associated with a single drug type (illicit drugs, alcohol, or pharmaceuticals). Illicit drugs alone were involved in 26.6 percent of drug misuse or abuse visits, pharmaceuticals alone were involved in 33.9 percent, and alcohol with no other drug (aged 20 or younger only) was involved in 4.8 percent. The remaining visits (34.7%) involved some combination of illicit drugs, alcohol, and pharmaceuticals.

Understanding that a visit may appear in more than one group, DAWN found that out of all ED visits involving drug misuse or abuse,

2.2 Trends in ED Visits Involving Drug Misuse or Abuse, 2004–2011

This section presents the trends in the estimates of ED visits involving drug misuse or abuse for the period from 2004 through 2011 (Table 3). Differences between years are presented in terms of the percentage increase or decrease in visits in 2011 compared with the estimates for 2004 (long-term trends) and for 2009 and 2010 (short-term trends). Only statistically significant changes are discussed and displayed in the table.

Table 3. Trends in ED visits involving drug misuse or abuse, by drug combinations, 2004–2011
Drug combinations (1) ED visits,
2004
ED visits,
2005
ED visits,
2006
ED visits,
2007
ED visits,
2008
ED visits,
2009
ED visits,
2010
ED visits,
2011
Percent
change,
2004,
2011 (2)
Percent
change,
2009,
2011 (2)
Percent
change,
2010,
2011 (2)
(1) The classification of drugs used in DAWN is derived from the Multum Lexicon, © 2012 Lexi-Comp, Inc. and/or Cerner Multum, Inc. The classification was modified to meet DAWN's unique requirements (2011). The Multum Licensing Agreement governing use of the Lexicon can be found on the DAWN Web site at http://www.samhsa.gov/data/dawn/MultumLicenseAgreement.pdf.
(2) This column denotes statistically significant (p < 0.05) increases or decreases between estimates for the periods shown.
(3) Estimates of ED visits are based on a representative sample of general, non-Federal, short-stay hospitals in the United States with 24-hour EDs.
(4) ED patients aged 21 or older for whom alcohol was the only drug associated with their ED visits are not considered DAWN cases.
(5) When present with other drugs, alcohol is reportable for patients of all ages.
NOTE: A dash (—) indicates a blank cell.
SOURCE: Center for Behavioral Health Statistics and Quality, SAMHSA, Drug Abuse Warning Network, 2011.
Total ED visits, overall drug misuse or abuse (3) 1,619,056 1,616,404 1,742,942 1,883,280 1,999,877 2,070,452 2,301,050 2,462,948   52 19
Illicit drug(s) only    502,864    518,223    537,271    522,966    510,911    476,521    584,270    656,025   — 38
Alcohol only (age < 21) (4)    150,988    110,599    126,705    137,375    132,859    138,614    122,778    117,653   —
Pharmaceutical(s) only    336,753    443,980    485,911    581,809    663,540    729,607    778,923    835,275 148
Combinations           —           —           —           —           —           —           —           —   —
Illicit drug(s) with alcohol (5)    338,733    222,268    219,830    238,190    229,704    211,712    249,608    261,125   —
Illicit drug(s) with pharmaceutical(s)    104,525    127,004    142,234    143,841    168,515    206,061    250,283    247,342 137
Alcohol with pharmaceutical(s) (5)    139,675    139,807    171,459    189,244    208,896    227,839    227,073    257,520   84
Illicit drug(s) with alcohol
and pharmaceutical(s) (5)
     45,517      54,523      59,531      69,855      85,453      80,099      88,115      88,008   93

In the long term, between 2004 and 2011, the annual overall number of ED visits attributable to drug misuse or abuse has risen steadily each year for a total increase of 52 percent, or about 844,000 visits. While visits involving illicit drugs alone or underage drinking have not risen, ED visits related to the use of pharmaceuticals with no other drug involvement rose substantially (148%), as did the use of pharmaceuticals with illicit drugs (137%), pharmaceuticals with alcohol (84%), and pharmaceuticals combined with both illicit drugs and alcohol (93%). These increases reflect almost 500,000 more ED visits related to pharmaceuticals alone in 2011 compared with 2004, over 142,000 more visits related to pharmaceuticals and illicit drugs, almost 120,000 more visits related to pharmaceuticals and alcohol, and over 42,000 more visits related to all three types of substances.

In the short term, between 2009 and 2011, ED visits involving overall drug misuse or abuse increased by 19 percent, or by about 200,000 visits per year for 2 years. Almost half of the net increase seen for ED visits involving misuse or abuse between 2004 and 2011 occurred in the last 2 years of the period. Unlike the long-term trends, though, which are largely driven by rises in pharmaceutical involvement, the short-term rise reflects the 38 percent increase seen in ED visits involving illicit drugs only, with no significant increases over the last 2 years for visits involving pharmaceuticals or alcohol alone or combinations of pharmaceuticals, alcohol, and illicit drugs.

3. ILLICIT DRUGS

3.1 ED Visits Involving Illicit Drugs, 2011

For analysis, DAWN groups together ED visits that involve illicit drugs. These substances include cocaine, heroin, marijuana, synthetic cannabinoids, amphetamines/methamphetamine, MDMA (Ecstasy), GHB (gamma-Hydroxybutyric acid), flunitrazepam (Rohypnol®), ketamine, LSD, PCP, and hallucinogens. Visits involving the inhalation of nonmedical substances for their psychoactive properties (e.g., sniffing model airplane glue) are also included.6

Of the approximately 2.5 million drug misuse or abuse ED visits that occurred during 2011, a total of 1,252,500, or just over half (50.9%), involved illicit drugs (Table 4). A majority (56.3%) of illicit drug ED visits involved multiple drugs. Overall, 27.9 percent of visits involving illicit drugs also involved alcohol.

Table 4. ED visits involving illicit drugs, 2011
Drugs (1) ED visits Percent of
ED visits
RSE (%) 95% CI:
Lower
bound
95% CI:
Upper
bound
(1) The classification of drugs used in DAWN is derived from the Multum Lexicon, © 2012 Lexi-Comp, Inc. and/or Cerner Multum, Inc. The classification was modified to meet DAWN's unique requirements (2011). The Multum Licensing Agreement governing use of the Lexicon can be found on the DAWN Web site at http://www.samhsa.gov/data/dawn/MultumLicenseAgreement.pdf.
(2) Estimates of ED visits are based on a representative sample of general, non-Federal, short-stay hospitals in the United States with 24-hour EDs.
(3) ED visits often involve multiple drugs. Such visits will appear multiple times in this table (e.g., a visit involving both cocaine and marijuana will appear twice in this table). The sum of visits by drug will be greater than the total, and the sum of percentages by drug will be greater than 100.
NOTE: CI = confidence interval. RSE = relative standard error. An asterisk (*) indicates that an estimate with a relative standard error greater than 50%, or an estimate based on fewer than 30 visits, has been suppressed.
SOURCE: Center for Behavioral Health Statistics and Quality, SAMHSA, Drug Abuse Warning Network, 2011.
Total ED visits, illicit drugs (2,3) 1,252,500 100.0 11.3 976,169 1,528,831
Single drug    547,945   43.7 13.6 402,408    693,482
Multiple drugs    704,555   56.3 11.5 546,064    863,046
Alcohol present    349,133   27.9 13.4 257,249    441,017
Cocaine    505,224   40.3 18.3 324,262    686,185
Heroin    258,482   20.6 10.5 205,046    311,918
Cannabinoids    479,560   38.3   9.0 394,921    564,198
Marijuana    455,668   36.4   9.5 370,995    540,340
Synthetic cannabinoids      28,531     2.3 18.1   18,390      38,672
Amphetamines/methamphetamine    159,840   12.8 19.0 100,199    219,481
Amphetamines      70,831     5.7 22.5   39,631    102,031
Methamphetamine    102,961     8.2 23.1   56,391    149,530
MDMA (Ecstasy)      22,498     1.8 10.2   17,981      27,015
GHB        2,406     0.2 20.3     1,448        3,364
Flunitrazepam (Rohypnol)               *        *      *            *               *
Ketamine        1,550     0.1 36.1        453        2,647
LSD        4,819     0.4 23.2     2,628        7,009
PCP      75,538     6.0 37.0   20,702    130,374
Misc. hallucinogens        8,043     0.6 20.6     4,792      11,294
Inhalants      10,032     0.8 25.0     5,109      14,956
Combinations not tabulated above      10,388     0.8 26.1     5,069      15,707

Cocaine and marijuana were the most commonly involved drugs, with 505,224 ED visits (40.3%) and 455,668 ED visits (36.4%), respectively. Cocaine and marijuana were followed by heroin, at 258,482 ED visits, or 20.6 percent, and then by amphetamines/methamphetamine, at 159,840 visits, or 12.8 percent.7

Other illicit drugs involved in ED visits occurred at levels under 5 percent and included the following:

The estimates for visits involving flunitrazepam (e.g., Rohypnol) was suppressed due to low statistical precision.

Synthetic cannabinoids, also known as "Spice" or "K2," appeared for the first time at reportable levels in DAWN in 2010; they were involved in 11,406 ED visits (1.0%). In 2011, a total of 28,531 ED visits, or 2.3 percent, involved synthetic cannabinoids. While there appears to be a number of different chemical compositions, synthetic cannabinoids are functionally similar to Δ9-tetrahydrocannabinol (THC), the active ingredient in cannabis.8 Users report effects similar to those produced by marijuana, and regular users may experience withdrawal and addiction symptoms.9 According to the Monitoring the Future survey, almost one in nine, or 11.4 percent, of high school seniors reported using synthetic cannabinoids in 2011.10,11

In 2011, there were 402.0 ED visits that involved illicit drugs for each 100,000 persons in the U.S. population (Table 5). The highest rates were found for cocaine involvement (162.1 ED visits per 100,000 population) and marijuana (146.2 visits) (Figure 2). These were followed by heroin (83.0 visits per 100,000 population), amphetamines/methamphetamine (51.3 visits), PCP (24.2 visits), synthetic cannabinoids (9.2 visits), and MDMA (Ecstasy) (7.2 visits). Lower-incidence drugs had rates below 4 visits per 100,000 population.

Table 5. Rates of ED visits per 100,000 population involving illicit drugs, 2011
Drugs (1) Rate of ED
visits per
100,000
population (2)
RSE (%) 95% CI:
Lower
bound
95% CI:
Upper
bound
(1) The classification of drugs used in DAWN is derived from the Multum Lexicon, © 2012 Lexi-Comp, Inc. and/or Cerner Multum, Inc. The classification was modified to meet DAWN's unique requirements (2011). The Multum Licensing Agreement governing use of the Lexicon can be found on the DAWN Web site at http://www.samhsa.gov/data/dawn/MultumLicenseAgreement.pdf.
(2) All rates are ED visits per 100,000 population. Estimates of ED visits are based on a representative sample of general, non-Federal, short-stay hospitals in the United States with 24-hour EDs. Population estimates are drawn from the set of United States Resident Population Estimates by Age, Sex, Race, and Hispanic Origin (Vintage 2011) issued by the U.S. Census Bureau.
(3) ED visits often involve multiple drugs. Such visits will appear multiple times in this table (e.g., a visit involving both cocaine and marijuana will appear twice in this table). The sum of visits by drug will be greater than the total, and the sum of percentages by drug will be greater than 100.
NOTE: CI = confidence interval. RSE = relative standard error. An asterisk (*) indicates that an estimate with a relative standard error greater than 50%, or an estimate based on fewer than 30 visits, has been suppressed.
SOURCE: Center for Behavioral Health Statistics and Quality, SAMHSA, Drug Abuse Warning Network, 2011.
Total ED visits, illicit drugs (3) 402.0 11.3 313.3 490.7
Cocaine 162.1 18.3 104.1 220.2
Heroin   83.0 10.5   65.8 100.1
Cannabinoids 153.9   9.0 126.7 181.1
Marijuana 146.2   9.5 119.1 173.4
Synthetic cannabinoids     9.2 18.1     5.9   12.4
Amphetamines/methamphetamine   51.3 19.0   32.2   70.4
Amphetamines   22.7 22.5   12.7   32.7
Methamphetamine   33.0 23.1   18.1   48.0
MDMA (Ecstasy)     7.2 10.2     5.8     8.7
GHB     0.8 20.3     0.5     1.1
Flunitrazepam (Rohypnol)        *      *        *        *
Ketamine     0.5 36.1     0.1     0.8
LSD     1.5 23.2     0.8     2.2
PCP   24.2 37.0     6.6   41.8
Misc. hallucinogens     2.6 20.6     1.5     3.6
Inhalants     3.2 25.0     1.6     4.8
Combinations not tabulated above     3.3 26.1     1.6     5.0

Figure 2. Rates of ED visits per 100,000 population involving illicit drugs, 2011

Figure 2     D

SOURCE: Center for Behavioral Health Statistics and Quality, SAMHSA, Drug Abuse Warning Network, 2011.

Table 6 presents estimates of the number of ED visits in 2011 involving illicit drugs, by sex, age, and race/ethnicity categories. To facilitate comparisons between demographic groups (e.g., comparing males to females), Table 7 and Figure 3 present the rates of ED visits per 100,000 population. For most illicit drugs, the rates were more than 50 percent higher for males than for females. Comparing visits by patient age, 21- to 24-year-olds had the highest rate of medical emergencies involving marijuana (446.9 visits per 100,000 population aged 21 to 24), heroin (266.1 visits), and amphetamines/methamphetamine (141.5 visits); 45- to 54-year-olds had the highest rate for cocaine (344.6 visits per 100,000 population aged 45 to 54).

Table 6. ED visits involving illicit drugs, by patient demographics, 2011
Patient demographics All illicits Cocaine Heroin Marijuana Amphetamines/
methamphet-
amine
MDMA
(Ecstasy)
GHB LSD PCP
(1) The classification of drugs used in DAWN is derived from the Multum Lexicon, © 2012 Lexi-Comp, Inc. and/or Cerner Multum, Inc. The classification was modified to meet DAWN's unique requirements (2011). The Multum Licensing Agreement governing use of the Lexicon can be found on the DAWN Web site at http://www.samhsa.gov/data/dawn/MultumLicenseAgreement.pdf.
(2) Estimates of ED visits are based on a representative sample of general, non-Federal, short-stay hospitals in the United States with 24-hour EDs.
(3) ED visits often involve multiple drugs. Such visits will appear multiple times in this table (e.g., a visit involving both cocaine and marijuana will appear twice in this table). The sum of visits by drug will be greater than the total, and the sum of percentages by drug will be greater than 100.
NOTE: An asterisk (*) indicates that an estimate with a relative standard error greater than 50%, or an estimate based on fewer than 30 visits, has been suppressed. A dash (—) indicates a blank cell.
SOURCE: Center for Behavioral Health Statistics and Quality, SAMHSA, Drug Abuse Warning Network, 2011.
Total ED visits, illicit drugs (1,2,3) 1,252,500 505,224 258,482 455,668 159,840 22,498 2,406 4,819 75,538
Sex             —         —         —          —          —        —      —      —        —
Male    810,055 325,396 167,016 298,016   99,755 15,612 1,408 4,045 51,906
Female    441,982 179,520   91,450 157,528   60,082   6,886    998    773 23,598
Unknown               *            *            *            *            *          *        *        *          *
Age             —         —         —          —          —        —      —      —        —
0–5 years        1,113            *            *            *            *          *        *        *          *
6–11 years        1,216            *            *            *            *          *        *        *          *
12–17 years      78,667     5,904     2,141   60,302     5,889   3,184        *        *   1,965
18–20 years    105,274   15,198   18,179   59,945   12,128   6,986        * 1,982   3,730
21–24 years    166,812   37,643   46,723   78,463   24,842   5,004        * 1,379 10,445
25–29 years    181,291   57,398   46,965   68,054   27,377   3,472    322        * 18,763
30–34 years    152,991   55,247   35,971   52,353   24,124   1,760        *        * 15,566
35–44 years    243,708 127,405   49,694   67,677   34,780   1,740    812        * 14,606
45–54 years    238,587 154,101   40,712   52,018   23,275          *        *        *          *
55–64 years      73,338   47,064   15,428   14,778     6,276          *        *        *      638
65 years and older        9,350     4,887     2,553     1,710        756          *        *        *          *
Unknown               *            *            *            *            *          *        *        *          *
Race/ethnicity             —         —         —          —          —        —      —      —        —
White    634,593 185,748 167,778 249,587 109,813 11,421 2,020 3,393 23,485
Black    384,317 236,089   36,095 122,081   13,231   4,352        *        * 43,599
Hispanic   136,888   49,810   31,031   49,593   25,483   3,089        *        *   3,677
Other/2+ race/ethnicities      18,318     5,086     3,290     7,314     3,556          *        *        *          *
Unknown      78,383   28,490   20,288   27,093     7,758   2,461    161    194   4,017
Table 7. Rates of ED visits per 100,000 population involving illicit drugs, by patient demographics, 2011
Patient demographics All illicits Cocaine Heroin Marijuana Amphetamines/
methamphet-
amine
MDMA
(Ecstasy)
GHB LSD PCP
(1) The classification of drugs used in DAWN is derived from the Multum Lexicon, © 2012 Lexi-Comp, Inc. and/or Cerner Multum, Inc. The classification was modified to meet DAWN's unique requirements (2011). The Multum Licensing Agreement governing use of the Lexicon can be found on the DAWN Web site at http://www.samhsa.gov/data/dawn/MultumLicenseAgreement.pdf.
(2) All rates are ED visits per 100,000 population. Estimates of ED visits are based on a representative sample of general, non-Federal, short-stay hospitals in the United States with 24-hour EDs. Population estimates are drawn from the set of United States Resident Population Estimates by Age, Sex, Race, and Hispanic Origin (Vintage 2011) issued by the U.S. Census Bureau.
(3) ED visits often involve multiple drugs. Such visits will appear multiple times in this table (e.g., a visit involving both cocaine and marijuana will appear twice in this table). The sum of visits by drug will be greater than the total, and the sum of percentages by drug will be greater than 100.
NOTE: An asterisk (*) indicates that an estimate with a relative standard error greater than 50%, or an estimate based on fewer than 30 visits, has been suppressed. A dash (—) indicates a blank cell. Rates are not provided for race and ethnicity subgroups because of data limitations.
SOURCE: Center for Behavioral Health Statistics and Quality, SAMHSA, Drug Abuse Warning Network, 2011.
Rates of ED visits, illicit drugs (1,2,3) 402.0 162.1   83.0 146.2   51.3   7.2 0.8   1.5 24.2
Sex      —      —      —      —      —    —  —    —    —
Male 528.4 212.3 109.0 194.4   65.1 10.2 0.9   2.6 33.9
Female 279.2 113.4   57.8   99.5   38.0   4.3 0.6   0.5 14.9
Age      —      —      —      —      —    —  —    —    —
0–5 years     4.6        *        *        *        *      *    *      *      *
6–11 years     4.9        *        *        *        *      *    *      *      *
12–17 years 313.3   23.5     8.5 240.2   23.5 12.7    *      *   7.8
18–20 years 779.4 112.5 134.6 443.8   89.8 51.7    * 14.7 27.6
21–24 years 950.1 214.4 266.1 446.9 141.5 28.5    *   7.9 59.5
25–29 years 851.9 269.7 220.7 319.8 128.7 16.3 1.5      * 88.2
30–34 years 745.9 269.4 175.4 255.2 117.6   8.6    *      * 75.9
35–44 years 599.9 313.6 122.3 166.6   85.6   4.3 2.0      * 35.9
45–54 years 533.5 344.6   91.0 116.3   52.0      *    *      *      *
55–64 years 192.7 123.7   40.5   38.8   16.5      *    *      *   1.7
65 years and older   22.6   11.8     6.2     4.1     1.8      *    *      *      *

Figure 3. Rates of ED visits per 100,000 population involving illicit drugs, by selected drugs, age, and sex, 2011

Figure 3     D

SOURCE: Center for Behavioral Health Statistics and Quality, SAMHSA, Drug Abuse Warning Network, 2011.

Considering race/ethnicity, 50.7 percent of patients were White, 30.7 percent were Black, 10.9 percent were Hispanic, 1.5 percent were of other or multiple race/ethnic groups, and 6.3 percent were of unknown race/ethnicity. DAWN does not produce population-based rates for race/ethnicity categories because race/ethnicity information is often missing from ED records.

Overall, 39.4 percent of visits involving illicit drugs resulted in some form of follow-up, including admission to the hospital (24.0%), transfer to another health care facility (9.6%), or referral to a drug detox/dependency program (5.8%) (Table 8). Most other patients (52.5%) were treated and released to home, with the remainder (8.1%) experiencing other outcomes.

Table 8. ED visits and rates involving illicit drugs, by patient disposition, 2011
Patient disposition ED visits Percent of ED visits Rate of ED visits
per 100,000
population (1)
(1) All rates are ED visits per 100,000 population. Population estimates are drawn from the set of United States Resident Population Estimates by Age, Sex, Race, and Hispanic Origin (Vintage 2011) issued by the U.S. Census Bureau.
(2) Estimates of ED visits are based on a representative sample of general, non-Federal, short-stay hospitals in the United States with 24-hour EDs.
NOTE: An asterisk (*) indicates that an estimate with a relative standard error greater than 50%, or an estimate based on fewer than 30 visits, has been suppressed.
SOURCE: Center for Behavioral Health Statistics and Quality, SAMHSA, Drug Abuse Warning Network, 2011.
Total ED visits, illicit drugs (2) 1,252,500 100.0 402.0
Treated and released    775,439   61.9 248.9
Discharged home    657,695   52.5 211.1
Released to police/jail      45,530     3.6   14.6
Referred to detox/treatment      72,214     5.8   23.2
Admitted to this hospital    300,342   24.0   96.4
ICU/critical care      29,780     2.4     9.6
Surgery        1,539     0.1     0.5
Chemical dependency/detox      24,517     2.0     7.9
Psychiatric unit      65,057     5.2   20.9
Other inpatient unit    179,449   14.3   57.6
Other disposition    176,718   14.1   56.7
Transferred    120,425     9.6   38.6
Left against medical advice      21,815     1.7     7.0
Died        1,502     0.1     0.5
Other      18,963     1.5     6.1
Not documented               *        *        *

3.2 Trends in ED Visits Involving Illicit Drugs, 2004–2011

This section presents the trends in the estimates of ED visits involving illicit drugs for the period from 2004 through 2011 (Table 9). Differences between years are presented in terms of the percentage increase or decrease in visits in 2011 compared with the estimates for 2004 (long-term trends) and for 2009 and 2010 (short-term trends). Only statistically significant changes are discussed and displayed in the table.

Table 9. Trends in ED visits involving illicit drugs, by selected drugs, 2004–2011
Drugs (1) ED visits,
2004
ED visits,
2005
ED visits,
2006
ED visits,
2007
ED visits,
2008
ED visits,
2009
ED visits,
2010
ED visits,
2011
Percent
change,
2004,
2011 (2)
Percent
change,
2009,
2011 (2)
Percent
change,
2010,
2011 (2)
(1) The classification of drugs used in DAWN is derived from the Multum Lexicon, © 2012 Lexi-Comp, Inc. and/or Cerner Multum, Inc. The classification was modified to meet DAWN's unique requirements (2011). The Multum Licensing Agreement governing use of the Lexicon can be found on the DAWN Web site at http://www.samhsa.gov/data/dawn/MultumLicenseAgreement.pdf.
(2) This column denotes statistically significant (p < 0.05) increases or decreases between estimates for the periods shown.
(3) Estimates of ED visits are based on a representative sample of general, non-Federal, short-stay hospitals in the United States with 24-hour EDs.
(4) ED visits often involve multiple drugs. Such visits will appear multiple times in this table (e.g., a visit involving both cocaine and marijuana will appear twice in this table). Thus, the sum of visits by drug will be greater than the total, and the sum of percentages by drug will be greater than 100.
NOTE: An asterisk (*) indicates that an estimate with a relative standard error greater than 50%, or an estimate based on fewer than 30 visits, has been suppressed. A dash (—) indicates a blank cell.
SOURCE: Center for Behavioral Health Statistics and Quality, SAMHSA, Drug Abuse Warning Network, 2011.
Total ED visits, illicit drugs (3,4) 991,640 922,018 958,866 974,852 994,583 974,392 1,172,276 1,252,500      29   
Cocaine 475,425 483,865 548,608 553,535 482,188 422,902    488,101    505,224   —   —   —
Heroin 214,432 187,493 189,787 188,162 200,666 213,118    224,706    258,482   —   —   —
Cannabinoids 281,619 279,668 290,568 308,547 374,443 376,494    470,845    479,560   70   27   —
Marijuana 281,619 279,668 290,568 308,547 374,443 376,492    461,028    455,668   62   —   —
Synthetic cannabinoids            *            *            *            *            *            *      11,406      28,531   —   — 150
Amphetamines/methamphetamine 162,435 137,806 107,586   85,043   91,945   93,564    138,632    159,840   —   71   —
Amphetamines   34,085   35,083   32,251   21,545   31,534   37,431      52,388      70,831   —   89   —
Methamphetamine 132,576 109,655   79,924   67,954   66,308   64,117      94,929    102,961   —   61   —
MDMA (Ecstasy)   10,227   11,287   16,784   12,751   17,888   22,847      21,836      22,498 120   —   —
GHB     1,789     1,036     1,084     2,210     1,441     1,758        1,787        2,406   —   —   —
Flunitrazepam (Rohypnol)            *            *            *            *            *        800           657               *   —   —   —
Ketamine            *        303        270        291        344        529           915        1,550   —   —   —
LSD     2,146     2,001     4,002     3,561     3,287     4,028        3,817        4,819   —   —   —
PCP   31,342   14,825   21,960   28,173   37,266   36,719      53,542      75,538   — 106   41
Misc. hallucinogens     3,153     3,194     3,900     4,899     6,193     6,620        6,107        8,043 155   —   —
Inhalants     9,525     5,167     5,650     7,996     7,115     6,137      11,401      10,032   —   —   —
Combinations not tabulated above            *     4,256     3,530     4,612     4,924     4,812        6,877      10,388   — 116   —

The overall level of ED visits involving illicit drugs was stable between 2004 and 2011, though several specific illicit drug categories experienced increased involvement over the 8 years. With 455,668 visits in 2011, marijuana experienced a 62 percent increase between 2004 and 2011. MDMA (Ecstasy) involvement more than doubled, reaching over 20,000 visits in 2011. The category of miscellaneous hallucinogens also more than doubled, with about 8,000 visits in 2011.

In the short term, between 2009 and 2011, illicit drugs overall as well as individual drugs have experienced significant increases. Contributing to the overall 29 percent 2-year increase in illicit drug involvement are rises in the involvement of synthetic cannabinoids, amphetamines, methamphetamine, PCP, and various combinations of these drugs. Synthetic cannabinoids first appeared in DAWN records in 2009, though at levels too small to be reported. By 2010, ED visits involving synthetic cannabinoids rose to a reportable level for the nation: 11,406 visits. By 2011, the number reached 28,531 visits, a 150 percent 1-year increase. Amphetamines involvement saw an 89 percent increase, and methamphetamine involvement had a 61 percent increase between 2009 and 2011 for a total of about 160,000 visits in 2011. PCP rose 106 percent over the 2 years, going from about 36,000 visits in 2009 to about 50,000 in 2010 and about 75,000 visits in 2011. Combination illicit drugs (e.g., cocaine/heroin combinations called "speedballs," marijuana mixed with PCP ["angel dust"]) increased 116 percent since 2009, reaching over 10,000 visits in 2011.

4. ALCOHOL

4.1 ED Visits Involving Drugs and Alcohol Taken Together, 2011

According to the National Institute on Alcohol Abuse and Alcoholism (NIAAA), more than 150 medications have harmful additive or interactive effects when combined with alcohol. The harmful effects of combining drugs with alcohol are heightened by drugs that depress the central nervous system, such as heroin, opiate pain relievers, benzodiazepines (anti-anxiety drugs), antihistamines, and antidepressants. These drug-alcohol interactions may result in increased risk of illness, injury, and even death. Medications for certain disorders—including diabetes, high blood pressure, and heart disease—also can have harmful interactions with alcohol.12

In 2011, over 600,000 ED visits involved drugs combined with alcohol (Table 10). This represents nearly a quarter of all ED visits associated with drug misuse or abuse.

Table 10. ED visits involving alcohol, 2011
Alcohol use category (1) ED visits (2) Percent of all
drug misuse/
abuse visits
RSE (%) 95% CI:
Lower
bound
95% CI:
Upper
bound
(1) The classification of drugs used in DAWN is derived from the Multum Lexicon, © 2012 Lexi-Comp, Inc. and/or Cerner Multum, Inc. The classification was modified to meet DAWN's unique requirements (2011). The Multum Licensing Agreement governing use of the Lexicon can be found on the DAWN Web site at http://www.samhsa.gov/data/dawn/MultumLicenseAgreement.pdf.
(2) Estimates of ED visits are based on a representative sample of general, non-Federal, short-stay hospitals in the United States with 24-hour EDs.
(3) For patients of all ages, DAWN records whether alcohol is present in addition to other drugs.
NOTE: CI = confidence interval. RSE = relative standard error.
SOURCE: Center for Behavioral Health Statistics and Quality, SAMHSA, Drug Abuse Warning Network, 2011.
Alcohol present with drugs (3) 606,653 24.6 9.9 489,228 724,078

Illicit drugs were involved in over half (57.6%) of ED visits involving alcohol-drug combinations, with cocaine and marijuana representing the greater proportions of such visits (28.6% and 25.0%, respectively) (Table 11). Pharmaceuticals were also involved in over half (57.0%) of such visits. Anxiolytics, sedatives, and hypnotics (drugs to treat insomnia and anxiety) were involved in 24.6 percent of visits, with the largest part of that category being benzodiazepines (20.4%). Pain relievers were involved in a similar number of visits (21.8%), with narcotic pain relievers accounting for over half of that number (12.6%). Psychotherapeutic agents (antidepressants and antipsychotics) were involved in 7.7 percent of visits involving alcohol-drug combinations.

Table 11. ED visits involving drugs and alcohol taken together, 2011
Drugs reported with alcohol (1) ED visits Percent of ED
visits
Rate of ED visits
per 100,000
population (2)
(1) The classification of drugs used in DAWN is derived from the Multum Lexicon, © 2012 Lexi-Comp, Inc. and/or Cerner Multum, Inc. The classification was modified to meet DAWN's unique requirements (2011). The Multum Licensing Agreement governing use of the Lexicon can be found on the DAWN Web site at http://www.samhsa.gov/data/dawn/MultumLicenseAgreement.pdf.
(2) All rates are ED visits per 100,000 population. Population estimates are drawn from the set of United States Resident Population Estimates by Age, Sex, Race, and Hispanic Origin (Vintage 2011) issued by the U.S. Census Bureau.
(3) Estimates of ED visits are based on a representative sample of general, non-Federal, short-stay hospitals in the United States with 24-hour EDs.
(4) All visits in this table involve alcohol and another drug. Some involve multiple drugs. Such visits will appear multiple times in this table (e.g., a visit involving alcohol, marijuana, and hydrocodone will appear twice in this table). The sum of visits by drug will be greater than the total, and the sum of percentages by drug will be greater than 100.
SOURCE: Center for Behavioral Health Statistics and Quality, SAMHSA, Drug Abuse Warning Network, 2011.
Total ED visits, drugs with alcohol (3,4) 606,653 100.0 194.7
Illicit drugs 349,133   57.6 112.0
Cocaine 173,799   28.6   55.8
Heroin   48,036     7.9   15.4
Cannabinoids 154,495   25.5   49.6
Marijuana 151,591   25.0   48.7
Synthetic cannabinoids     3,806     0.6     1.2
Amphetamines/methamphetamine   25,820     4.3     8.3
Pharmaceuticals 345,528   57.0 110.9
Anxiolytics, sedatives, and hypnotics 148,958   24.6   47.8
Benzodiazepines 123,572   20.4   39.7
Alprazolam   46,713     7.7   15.0
Clonazepam   25,322     4.2     8.1
Lorazepam   15,539     2.6     5.0
Central nervous system stimulants (e.g., ADHD drugs)   17,118     2.8     5.5
Pain relievers 131,991   21.8   42.4
Acetaminophen products   15,082     2.5     4.8
Opiates/opioids 103,730   17.1   33.3
Narcotic pain relievers   76,734   12.6   24.6
Hydrocodone products   25,712     4.2     8.3
Oxycodone products   31,534     5.2   10.1
Psychotherapeutic agents   46,949     7.7   15.1
Antidepressants   33,854     5.6   10.9
Antipsychotics   19,409     3.2     6.2

Looking at alcohol involvement from the perspective of all visits involving drug misuse or abuse, DAWN found that about 30 percent of visits involving illicit drugs also involved alcohol (Table 12). Among illicit drugs, higher levels of alcohol involvement were found for visits involving ketamine (71.5%). Among visits involving pharmaceuticals, about 25 percent also involved alcohol. Alcohol was present in 38.6 percent of visits involving penicillin, 37.9 percent of visits involving central nervous system (CNS) stimulants (e.g., ADHD drugs), and 31.2 percent of visits involving antidepressants.

Table 12. ED visits involving alcohol, by drug, 2011
Drugs category and selected drugs (1) All ED visits
involving drug
Percent also
involving alcohol
(1) The classification of drugs used in DAWN is derived from the Multum Lexicon, © 2012 Lexi-Comp, Inc. and/or Cerner Multum, Inc. The classification was modified to meet DAWN's unique requirements (2011). The Multum Licensing Agreement governing use of the Lexicon can be found on the DAWN Web site at http://www.samhsa.gov/data/dawn/MultumLicenseAgreement.pdf.
(2) Estimates of ED visits are based on a representative sample of general, non-Federal, short-stay hospitals in the United States with 24-hour EDs.
(3) All visits in this table involve alcohol and another drug. Some involve multiple drugs. Such visits will appear multiple times in this table (e.g., a visit involving alcohol, marijuana, and antidepressants will appear twice in this table). The sum of visits by drug will be greater than the total, and the sum of percentages by drug will be greater than 100.
SOURCE: Center for Behavioral Health Statistics and Quality, SAMHSA, Drug Abuse Warning Network, 2011.
Total ED visits, drug misuse or abuse (2,3) 2,462,948 29.4
Illicit drugs 1,252,500 27.9
Cocaine    505,224 34.4
Heroin    258,482 18.6
Marijuana    455,668 33.3
Amphetamines/methamphetamine    159,840 16.2
MDMA (Ecstasy)      22,498 39.6
GHB        2,406 35.8
Ketamine        1,550 71.5
LSD        4,819 34.2
Misc. hallucinogens        8,043 33.3
Inhalants      10,032 23.4
Pharmaceuticals 1,428,145 24.2
Anticonvulsants      53,142 28.3
Antidepressants    108,388 31.2
Antihistamines        9,553 24.6
Antipsychotics      76,197 25.5
Anxiolytics, sedatives, and hypnotics    501,207 29.7
Benzodiazepines    425,616 29.0
Central nervous system stimulants (e.g., ADHD drugs)      45,158 37.9
Muscle relaxants      52,830 18.0
Pain relievers    662,400 19.9
Aspirin products      13,594 24.2
Narcotic pain relievers    420,040 18.3
Nonsteroidal anti-inflammatories (NSAIDs)      42,065 25.0
Penicillins        4,296 38.6
Respiratory agents      46,819 27.8

There were 194.7 visits per 100,000 population that involved drugs in combination with alcohol (Table 13). The rate of drug-related ED visits involving alcohol was higher for males (249.5 visits per 100,000 males) than for females (141.5 visits; Figure 4). By age, the highest rate of alcohol involvement was found for those aged 21 to 24 (393.9 visits per 100,000 population aged 21 to 24), though alcohol involvement was consistently near or above 300 visits per 100,000 population for all the age groups between 21 and 54.

Table 13. ED visits involving drugs and alcohol taken together, by patient demographics, 2011
Patient demographics ED visits Percent of ED
visits
Rate of ED visits
per 100,000
population (1)
(1) All rates are ED visits per 100,000 population. Population estimates are drawn from the set of United States Resident Population Estimates by Age, Sex, Race, and Hispanic Origin (Vintage 2011) issued by the U.S. Census Bureau.
(2) Estimates of ED visits are based on a representative sample of general, non-Federal, short-stay hospitals in the United States with 24-hour EDs.
NOTE: An asterisk (*) indicates that an estimate with a relative standard error greater than 50%, or an estimate based on fewer than 30 visits, has been suppressed. A dash (—) indicates a blank cell. Rates are not provided for race and ethnicity subgroups because of data limitations.
SOURCE: Center for Behavioral Health Statistics and Quality, SAMHSA, Drug Abuse Warning Network, 2011.
Total ED visits, drugs and alcohol (2) 606,653 100.0 194.7
Sex          —      —      —
Male 382,438   63.0 249.5
Female 223,987   36.9 141.5
Unknown            *        *        *
Age          —      —      —
0–5 years            *        *        *
6–11 years            *        *        *
12–17 years   31,752     5.2 126.5
18–20 years   38,897     6.4 288.0
21–24 years   69,159   11.4 393.9
25–29 years   74,941   12.4 352.2
30–34 years   75,332   12.4 367.3
35–44 years 122,706   20.2 302.0
45–54 years 133,771   22.1 299.1
55–64 years   50,388     8.3 132.4
65 years and older     9,190     1.5   22.2
Unknown            *        *        *
Race/ethnicity          —      —      —
White 356,004   58.7      —
Black 135,296   22.3      —
Hispanic   66,174   10.9      —
Other or two or more race/ethnicities     8,042     1.3      —
Unknown   41,137     6.8      —

Figure 4. Rates of ED visits per 100,000 population involving drugs and alcohol, by age and sex, 2011

Figure 4     D

SOURCE: Center for Behavioral Health Statistics and Quality, SAMHSA, Drug Abuse Warning Network, 2011.

Considering race/ethnicity, 58.7 percent of patients were White, 22.3 percent were Black, 10.9 percent were Hispanic, 1.3 percent were of other or multiple race/ethnic groups, and 6.8 percent were of unknown race/ethnicity. DAWN does not produce population-based rates for race/ethnicity categories because race/ethnicity information is often missing from ED records.

Just under half (45.4%) of patients seen for alcohol-related ED visits received follow-up care: 27.2 percent were admitted to the hospital, 12.0 percent were transferred to another facility, and the balance (6.3%) was referred to detox/treatment (Table 14). The remaining patients were treated and released to home (48.4%) or had other outcomes (6.2%).

Table 14. ED visits involving drugs and alcohol taken together, by patient disposition, 2011
Patient disposition ED visits Percent of ED visits Rate of ED visits per
100,000 population (1)
(1) All rates are ED visits per 100,000 population. Population estimates are drawn from the set of United States Resident Population Estimates by Age, Sex, Race, and Hispanic Origin (Vintage 2011) issued by the U.S. Census Bureau.
(2) Estimates of ED visits are based on a representative sample of general, non-Federal, short-stay hospitals in the United States with 24-hour EDs.
NOTE: An asterisk (*) indicates that an estimate with a relative standard error greater than 50%, or an estimate based on fewer than 30 visits, has been suppressed.
SOURCE: Center for Behavioral Health Statistics and Quality, SAMHSA, Drug Abuse Warning Network, 2011.
Total ED visits, drugs with alcohol (2) 606,653 100.0 194.7
Treated and released 346,469   57.1 111.2
Discharged home 293,612   48.4   94.2
Released to police/jail   14,834     2.4     4.8
Referred to detox/treatment   38,022     6.3   12.2
Admitted to this hospital 165,043   27.2   53.0
ICU/critical care   30,925     5.1     9.9
Surgery        374     0.1     0.1
Chemical dependency/detox   13,538     2.2     4.3
Psychiatric unit   36,611     6.0   11.7
Other inpatient unit   83,595   13.8   26.8
Other disposition   95,142   15.7   30.5
Transferred   72,601   12.0   23.3
Left against medical advice     8,288     1.4     2.7
Died            *        *        *
Other     7,840     1.3     2.5
Not documented            *        *        *

4.2 Underage Drinking

The use of alcohol by those under the age of 21 can have many immediate adverse consequences as well as lead to dangerous patterns of alcohol abuse in adulthood. Intervention at an early age is critical to preventing these patterns from developing. Intervention during an ED visit may be an efficient way to identify those youth at higher risk.

In 2011, of the nearly 440,000 drug abuse–related ED visits made by patients aged 20 or younger, almost half (188,706 visits, or 43.2%) involved alcohol (Table 15).

Table 15. ED visits involving underage drinking, 2011
Alcohol use category (1) ED visits (2) Percent of
drug misuse/
abuse visits
made by
patients < 21
RSE (%) 95% CI:
Lower
bound
95% CI:
Upper
bound
(1) The classification of drugs used in DAWN is derived from the Multum Lexicon, © 2012 Lexi-Comp, Inc. and/or Cerner Multum, Inc. The classification was modified to meet DAWN's unique requirements (2011). The Multum Licensing Agreement governing use of the Lexicon can be found on the DAWN Web site at http://www.samhsa.gov/data/dawn/MultumLicenseAgreement.pdf.
(2) Estimates of ED visits are based on a representative sample of general, non-Federal, short-stay hospitals in the United States with 24-hour EDs.
(3) Underage drinking includes ED visits for patients aged 20 or younger that involve alcohol with or without concurrent use of other drugs.
NOTE: CI = confidence interval. RSE = relative standard error.
SOURCE: Center for Behavioral Health Statistics and Quality, SAMHSA, Drug Abuse Warning Network, 2011.
Underage drinking (3) 188,706 43.2 9.6 153,216 224,196

Of these ED visits involving underage drinking, 71,991 visits were made by patients aged 12 to 17, and 115,841 visits were made by patients aged 18 to 20 (Table 16). Considering rates, though, the difference is more striking. The rate of medical emergencies involving use of alcohol was 286.7 visits per 100,000 population aged 12 to 17 and 857.6 per 100,000 population aged 18 to 20, almost a threefold difference. For those aged 18 to 20, about two thirds of these visits involved just alcohol, with the remainder involving alcohol taken with other drugs (Figure 5). The visits were more evenly split between alcohol alone and alcohol in combination with drugs for those aged 12 to 17.

Table 16. ED visits involving alcohol, by patients aged 12 to 17 and 18 to 20, 2011
Alcohol use category (1) ED
visits (2)
Rate of ED
visits per
100,000
population (3)
RSE (%) 95% CI:
Lower bound
95% CI:
Upper bound
(1) The classification of drugs used in DAWN is derived from the Multum Lexicon, © 2012 Lexi-Comp, Inc. and/or Cerner Multum, Inc. The classification was modified to meet DAWN's unique requirements (2011). The Multum Licensing Agreement governing use of the Lexicon can be found on the DAWN Web site at http://www.samhsa.gov/data/dawn/MultumLicenseAgreement.pdf.
(2) Estimates of ED visits are based on a representative sample of general, non-Federal, short-stay hospitals in the United States with 24-hour EDs.
(3) All rates are ED visits per 100,000 population. Population estimates are drawn from the set of United States Resident Population Estimates by Age, Sex, Race, and Hispanic Origin (Vintage 2011) issued by the U.S. Census Bureau.
NOTE: CI = confidence interval. RSE = relative standard error.
SOURCE: Center for Behavioral Health Statistics and Quality, SAMHSA, Drug Abuse Warning Network, 2011.
Alcohol abuse, patients aged 12 to 17   71,991 286.7   9.7 58,327   85,655
Alcohol with drugs   31,752 126.5 14.4 22,808   40,696
Alcohol alone   40,239 160.3 10.0 32,339   48,139
Alcohol abuse, patients aged 18 to 20 115,841 857.6 11.5 89,722 141,960
Alcohol with drugs   38,897 288.0 13.7 28,480   49,314
Alcohol alone   76,945 569.7 13.0 57,347   96,542

Figure 5. Rates of ED visits per 100,000 population involving alcohol, by patients aged 12 to 17 and 18 to 20, 2011

Figure 5     D

SOURCE: Center for Behavioral Health Statistics and Quality, SAMHSA, Drug Abuse Warning Network, 2011.

4.3 Trends in ED Visits Involving Alcohol, 2004–2011

This section presents the trends in the estimates of ED visits involving alcohol for the period from 2004 through 2011 (Table 17). Differences between years are presented in terms of the percentage increase or decrease in visits in 2011 compared with the estimates for 2004 (long-term trends) and for 2009 and 2010 (short-term trends). Only statistically significant changes are discussed and displayed in the table.

Table 17. Trends in ED visits involving alcohol, 2004–2011
Alcohol use
category (1,2)
ED visits,
2004
ED visits,
2005
ED visits,
2006
ED visits,
2007
ED visits,
2008
ED visits,
2009
ED visits,
2010
ED visits,
20111
Percent
change,
2004,
2011 (3)
Percent
change,
2009,
2011 (3)
Percent
change,
2010,
2011 (3)
(1) The classification of drugs used in DAWN is derived from the Multum Lexicon, © 2012 Lexi-Comp, Inc. and/or Cerner Multum, Inc. The classification was modified to meet DAWN's unique requirements (2011). The Multum Licensing Agreement governing use of the Lexicon can be found on the DAWN Web site at http://www.samhsa.gov/data/dawn/MultumLicenseAgreement.pdf.
(2) Estimates of ED visits are based on a representative sample of general, non-Federal, short-stay hospitals in the United States with 24-hour EDs.
(3) This column denotes statistically significant (p < 0.05) increases or decreases between estimates for the periods shown.
(4) For patients of all ages, DAWN always records whether alcohol is involved in a drug-related visit. ED visits involving alcohol and no other drugs are reportable to DAWN only if the patient is aged 20 or younger. DAWN estimates do not represent visits involving just alcohol for adults aged 21 or older.
(5) Underage drinking includes ED visits for patients aged 20 or younger that involve alcohol with or without concurrent use of other drugs.
NOTE: A dash (—) indicates a blank cell.
SOURCE: Center for Behavioral Health Statistics and Quality, SAMHSA, Drug Abuse Warning Network, 2011.
Alcohol with drugs (all ages) (4) 523,926 416,599 450,820 497,288 524,052 519,650 564,796 606,653
Underage drinking (5) 204,910 158,393 183,260 196,208 190,015 199,429 189,060 188,706
Patients aged 12 to 17   67,589   62,459   76,760   82,364   74,991   76,918   73,716   71,991
Patients aged 18 to 20 135,313   95,166 105,675 112,563 113,993 120,853 114,722 115,841

Involvement of alcohol in drug-related medical emergencies has remained stable over the period from 2004 through 2011. Underage drinking has, likewise, remained constant for youth aged 12 to 17 and young adults aged 18 to 20.

5. NONMEDICAL USE OF PHARMACEUTICALS

5.1 ED Visits Involving Nonmedical Use of Pharmaceuticals, 2011

There is growing concern in the public health community about the misuse or abuse of pharmaceuticals. When taken as directed for legitimate medical purposes, pharmaceuticals are usually safe and effective. However, when misused, pharmaceuticals can be just as dangerous and debilitating as illegal drugs.13 As documented by the 2011 National Survey of Drug Use and Health (NSDUH), misuse of pharmaceuticals appears to be widespread. NSDUH estimated that over 14 million persons aged 12 or older used prescription-type pain relievers, tranquilizers, stimulants, or sedatives nonmedically in 2011.14 Of the estimated 3.1 million persons aged 12 or older in 2011 who misused or abused drugs for the first time within the past 12 months, more than one in five initiated with nonmedical use of psychotherapeutics (22.0%, including 14.0% with pain relievers, 4.2% with tranquilizers, 2.6% with stimulants, and 1.2% with sedatives). Initiation rates for nonmedical pain reliever use continued to be second only to marijuana rates. NSDUH also reported that about 700,000 persons received treatment in the past year for use of pain relievers, exceeding the number for cocaine (511,000 persons), heroin (430,000 persons), or tranquilizers (300,000 persons).

DAWN defines nonmedical use to include misuse or abuse of any therapeutic substance. While use of any illicit drug is assumed to constitute drug abuse, nonmedical use of pharmaceuticals must be substantiated in the patient's ED medical records. Evidence supporting nonmedical use includes the following:

Nonmedical use of pharmaceuticals may involve a single pharmaceutical, multiple pharmaceuticals, or pharmaceuticals in combination with illicit drugs or alcohol. Pharmaceuticals that the patient may have taken recently but that are not related to the reason for the ED visit are not included in the DAWN data.15

For 2011, DAWN estimates that 1,244,872 ED visits involved nonmedical use of prescription medicines, over-the-counter drugs, or other types of pharmaceuticals (Table 18). This represents about a quarter (24.6%) of all drug-related ED visits and about half (50.5%) of ED visits for drug abuse or misuse. Over half (53.0%) of medical emergencies seen in the ED resulting from nonmedical use of pharmaceuticals involved multiple drugs.16 About one in five (17.6%) of ED visits involving nonmedical use of pharmaceuticals also involved alcohol.

Table 18. ED visits involving nonmedical use of pharmaceuticals, by selected drugs, 2011
Drug category and selected drugs (1) ED
visits
Percent of
ED
visits
RSE (%) 95% CI:
Lower
bound
95% CI:
Upper
bound
(1) The classification of drugs used in DAWN is derived from the Multum Lexicon, © 2012 Lexi-Comp, Inc. and/or Cerner Multum, Inc. The classification was modified to meet DAWN's unique requirements (2011). The Multum Licensing Agreement governing use of the Lexicon can be found on the DAWN Web site at http://www.samhsa.gov/data/dawn/MultumLicenseAgreement.pdf.
(2) Estimates of ED visits are based on a representative sample of general, non-Federal, short-stay hospitals in the United States with 24-hour EDs.
(3) ED visits often involve multiple drugs. Such visits will appear multiple times in this table (e.g., a visit involving both methadone and tramadol will appear twice in this table). The sum of visits by drug will be greater than the total, and the sum of percentages by drug will be greater than 100.
NOTE: CI = confidence interval. RSE = relative standard error.
SOURCE: Center for Behavioral Health Statistics and Quality, SAMHSA, Drug Abuse Warning Network, 2011.
Total ED visits, nonmedical use (2,3) 1,244,872 100.0   7.2 1,068,306 1,421,438
Single drug    585,367   47.0   6.4    512,368    658,366
Multiple drugs    659,505   53.0   9.9    532,058    786,953
Alcohol present    219,485   17.6 10.3    174,981    263,989
Pharmaceuticals 1,244,872 100.0   7.2 1,068,306 1,421,438
Anorexiants        1,042     0.1 32.8           372        1,711
Anticonvulsants      44,235     3.6 10.7      34,924      53,547
Anti-Parkinson agents        6,200     0.5 29.4        2,629        9,772
Anxiolytics, sedatives, and hypnotics    421,940   33.9 11.9    323,813    520,067
Barbiturates      18,282     1.5 14.1      13,224      23,341
Benzodiazepines    357,836   28.7 14.3    257,887    457,784
Alprazolam    123,744     9.9 15.1      87,050    160,439
Clonazepam      61,219     4.9   6.7      53,121      69,317
Diazepam      24,118     1.9   8.8      19,951      28,285
Lorazepam      42,874     3.4   8.8      35,510      50,238
Diphenhydramine      19,012     1.5 19.7      11,664      26,359
Hydroxyzine        4,978     0.4 20.2        3,003        6,954
Zolpidem      30,149     2.4   8.0      25,402      34,896
Cardiovascular agents      47,699     3.8   9.0      39,256      56,143
ACE inhibitors        6,980     0.6 14.0        5,070        8,890
Alpha agonists, central        9,080     0.7 22.8        5,022      13,139
Beta blockers      14,585     1.2 10.7      11,528      17,642
Calcium channel blocking agents        7,043     0.6 18.3        4,523        9,563
Diuretics        7,829     0.6 17.4        5,157      10,501
Central nervous system stimulants      40,648     3.3 12.3      30,835      50,461
Amphetamine-dextroamphetamine      17,272     1.4 14.8      12,277      22,268
Caffeine        1,848     0.1 40.9           368        3,329
Methylphenidate        4,918     0.4 25.4        2,469        7,366
Gastrointestinal agents      13,060     1.0 15.1        9,192      16,929
Hormones      12,539     1.0 16.6        8,454      16,625
Metabolic agents      27,794     2.2 11.3      21,623      33,965
Muscle relaxants      46,269     3.7 11.5      35,826      56,711
Carisoprodol      25,528     2.1 16.9      17,085      33,970
Cyclobenzaprine      11,551     0.9 15.2        8,121      14,981
Nutritional products      11,090     0.9 14.1        8,036      14,144
Pain relievers    573,497   46.1   9.5    466,963    680,031
Acetaminophen products      39,783     3.2   6.2      34,925      44,642
Aspirin products      11,074     0.9 17.1        7,365      14,783
Nonsteroidal anti-inflammatories      33,034     2.7   6.5      28,847      37,220
Ibuprofen      22,663     1.8   9.0      18,671      26,655
Naproxen        7,223     0.6 24.4        3,771      10,675
Opiates/opioids    488,004   39.2 10.7    386,007    590,001
Narcotic pain relievers    366,181   29.4   9.2    300,358    432,004
Buprenorphine products      21,483     1.7 21.1      12,600      30,366
Codeine products        9,927     0.8 19.5        6,141      13,712
Fentanyl products      20,034     1.6 19.7      12,294      27,774
Hydrocodone products      82,480     6.6   9.3      67,502      97,457
Hydromorphone products      18,224     1.5 17.2      12,081      24,366
Methadone      66,870     5.4 11.0      52,487      81,253
Morphine products      34,593     2.8 10.5      27,498      41,689
Oxycodone products    151,218   12.1 16.5    102,455    199,981
Propoxyphene products        1,655     0.1 36.9           459        2,851
Opiates/opioids, unspecified    138,130   11.1 20.3      83,228    193,031
Tramadol products      20,000     1.6 18.6      12,693      27,307
Psychotherapeutic agents    135,455   10.9   7.2    116,470    154,441
Antidepressants      88,965     7.1   7.0      76,681    101,249
SSRI antidepressants      41,257     3.3   6.9      35,700      46,814
Tricyclic antidepressants      15,307     1.2 22.2        8,634      21,980
Antipsychotics      61,951     5.0 11.4      48,094      75,809
Respiratory agents      41,377     3.3   9.9      33,361      49,393
Antihistamines        8,441     0.7 17.8        5,496      11,386
Bronchodilators        3,762     0.3 23.3        2,045        5,479
Expectorants        5,336     0.4 24.4        2,787        7,886
Upper respiratory products      17,726     1.4 13.3      13,094      22,359

At 46.1 percent, pain relievers were the most common type of drugs involved in medical emergencies associated with nonmedical use of pharmaceuticals; narcotic pain relievers were involved in 29.4 percent. Specific narcotic pain relievers seen more commonly were oxycodone, hydrocodone, and methadone at 12.1, 6.6, and 5.4 percent, respectively.17 Non-narcotic pain relievers—such as acetaminophen, nonsteroidal anti-inflammatories (e.g., ibuprofen, naproxen), and aspirin—were seen at levels below 4 percent.

Anxiolytics, sedatives, and hypnotics (drugs to treat anxiety and insomnia) were found in 33.9 percent of visits related to nonmedical use of pharmaceuticals. Benzodiazepines were involved in 28.7 percent of ED visits, with alprazolam (e.g., Xanax) indicated in about a third (9.9%) of such visits.

Among other major categories of drugs, psychotherapeutic agents (antidepressants and antipsychotics) were involved in 10.9 percent of ED visits related to nonmedical use of pharmaceuticals. Central nervous system (CNS) stimulants (e.g., ADHD drugs), respiratory agents, cardiovascular agents, muscle relaxants, and anticonvulsants each were involved in about 3 to 4 percent of ED visits. Other types of drugs were found in under 2 percent of visits.

When population size and sampling error are taken into account, visits for nonmedical use of pharmaceuticals did not differ between males and females (399.0 and 399.7 visits per 100,000 population, respectively; Table 19, Figure 6). The rate of ED visits for patients in age categories between 21 and 29 were over 700 visits per 100,000 population, with lower levels observed for younger and older patients.

Table 19. ED visits and rates involving nonmedical use of pharmaceuticals, by patient demographics, 2011
Patient demographics ED visits Percent of ED
visits
Rate of ED visits
per 100,000
population (1)
(1) All rates are ED visits per 100,000 population. Population estimates are drawn from the set of United States Resident Population Estimates by Age, Sex, Race, and Hispanic Origin (Vintage 2011) issued by the U.S. Census Bureau.
(2) Estimates of ED visits are based on a representative sample of general, non-Federal, short-stay hospitals in the United States with 24-hour EDs.
NOTE: An asterisk (*) indicates that an estimate with a relative standard error greater than 50% or an estimate based on fewer than 30 visits has been suppressed. A dash (—) indicates a blank cell. Rates are not provided for race and ethnicity subgroups because of data limitations.
SOURCE: Center for Behavioral Health Statistics and Quality, SAMHSA, Drug Abuse Warning Network, 2011.
Total ED visits, nonmedical use (2) 1,244,872 100.0 399.5
Sex             —      —      —
Male    611,680   49.1 399.0
Female    632,788   50.8 399.7
Unknown               *        *        *
Age             —      —      —
0–5 years        9,808     0.8   40.4
6–11 years        4,351     0.3   17.7
12–17 years      75,487     6.1 300.6
18–20 years      76,896     6.2 569.3
21–24 years    128,918   10.4 734.3
25–29 years    156,230   12.5 734.2
30–34 years    140,254   11.3 683.8
35–44 years    215,897   17.3 531.4
45–54 years    216,641   17.4 484.5
55–64 years    125,370   10.1 329.4
65 years and older      94,322     7.6 227.9
Unknown               *        *        *
Race/ethnicity             —      —      —
White    897,976   72.1      —
Black    146,190   11.7      —
Hispanic    104,211     8.4      —
Other or two or more race/ethnicities      20,680     1.7      —
Unknown      75,815     6.1      —

Figure 6. Rates of ED visits per 100,000 population involving nonmedical use of pharmaceuticals, by age and sex, 2011

Figure 6     D

SOURCE: Center for Behavioral Health Statistics and Quality, SAMHSA, Drug Abuse Warning Network, 2011.

In terms of race/ethnicity, 72.1 percent of visits related to nonmedical use of pharmaceuticals involved patients who were White, 11.7 percent who were Black, and 8.4 percent who were Hispanic. DAWN does not produce population-based rates for race/ethnicity categories because race/ethnicity information is often missing from ED records.

Some form of follow-up was observed for 38.0 percent of patients whose visits involved nonmedical use of pharmaceuticals (Table 20). Follow-up included admission to the hospital (25.8%), transfer to another facility (9.6%), and referral to detox/treatment (2.6%). Of the remainder, 56.2 percent of patients were treated and released to home, and 5.7 percent had other outcomes. This distribution of outcomes is similar to that found for patients whose ED visits involved illicit drugs (see Table 8).

Table 20. ED visits and rates involving nonmedical use of pharmaceuticals, by patient disposition, 2011
Patient disposition ED visits Percent of ED
visits
Rate of ED visits
per 100,000
population (1)
(1) All rates are ED visits per 100,000 population. Population estimates are drawn from the set of United States Resident Population Estimates by Age, Sex, Race, and Hispanic Origin (Vintage 2011) issued by the U.S. Census Bureau.
(2) Estimates of ED visits are based on a representative sample of general, non-Federal, short-stay hospitals in the United States with 24-hour EDs.
NOTE: An asterisk (*) indicates that an estimate with a relative standard error greater than 50%, or an estimate based on fewer than 30 visits, has been suppressed.
SOURCE: Center for Behavioral Health Statistics and Quality, SAMHSA, Drug Abuse Warning Network, 2011.
Total ED visits, nonmedical use (2) 1,244,872 100.0 399.5
Treated and released    754,866   60.6 242.3
Discharged home    700,018   56.2 224.7
Released to police/jail      22,175     1.8     7.1
Referred to detox/treatment      32,673     2.6   10.5
Admitted to this hospital    320,980   25.8 103.0
ICU/critical care      73,894     5.9   23.7
Surgery           443     0.0     0.1
Chemical dependency/detox        2,107     0.2     0.7
Psychiatric unit      42,544     3.4   13.7
Other inpatient unit    201,992   16.2   64.8
Other disposition    169,026   13.6   54.2
Transferred    119,830     9.6   38.5
Left against medical advice      21,717     1.7     7.0
Died        2,160     0.2     0.7
Other      14,081     1.1     4.5
Not documented               *        *        *

5.2 Trends in ED Visits Involving Nonmedical Use of Pharmaceuticals, 2004–2011

This section presents the trends in the estimates of ED visits involving nonmedical use of pharmaceuticals for the period from 2004 through 2011 (Table 21). Differences between years are presented in terms of the percentage increase or decrease in visits in 2011 compared with the estimates for 2004 (long-term trends) and for 2009 and 2010 (short-term trends). Only statistically significant changes are discussed and displayed in the table.

Table 21. Trends in ED visits involving nonmedical use of pharmaceuticals, by selected drugs, 2004–2011
Drug category and selected drugs (1) ED visits,
2004
ED visits,
2005
ED visits,
2006
ED visits,
2007
ED visits,
2008
ED visits,
2009
ED visits,
2010
ED visits,
2011
Percent
change,
2004,
2011 (2)
Percent
change,
2009,
2011 (2)
Percent
change,
2010,
2011 (2)
(1) The classification of drugs used in DAWN is derived from the Multum Lexicon, © 2012 Lexi-Comp, Inc. and/or Cerner Multum, Inc. The classification was modified to meet DAWN's unique requirements (2011). The Multum Licensing Agreement governing use of the Lexicon can be found on the DAWN Web site at http://www.samhsa.gov/data/dawn/MultumLicenseAgreement.pdf.
(2) This column denotes statistically significant (p < 0.05) increases or decreases between estimates for the periods shown.
(3) Estimates of ED visits are based on a representative sample of general, non-Federal, short-stay hospitals in the United States with 24-hour EDs.
(4) ED visits often involve multiple drugs. Such visits will appear multiple times in this table (e.g., a visit involving both methadone and tramadol will appear twice in this table). The sum of visits by drug will be greater than the total, and the sum of percentages by drug will be greater than 100.
NOTE: An asterisk (*) indicates that an estimate with a relative standard error greater than 50%, or an estimate based on fewer than 30 visits, has been suppressed. A dash (—) indicates a blank cell.
SOURCE: Center for Behavioral Health Statistics and Quality, SAMHSA, Drug Abuse Warning Network, 2011.
Total ED visits, nonmedical use (3,4) 535,447 668,211 740,457 855,334 970,657 1,078,714 1,172,403 1,244,872 132   15
Pharmaceuticals 535,447 668,211 740,457 855,334 970,657 1,078,714 1,172,403 1,244,872 132   15
Anorexiants            *     1,757     1,170        851     1,660        1,698        2,144        1,042   —   —
Anticonvulsants   28,655   27,645   31,169   35,403   37,445      42,073      43,934      44,235   —   —
Anti-Parkinson agents     2,472     1,692     3,816     3,764     3,802        4,775        3,532        6,200   —   —
Anxiolytics, sedatives, and hypnotics 177,409 227,489 233,886 259,988 325,105    363,270    399,061    421,940 138   —
Barbiturates   11,721   14,693   10,991     9,877     9,603      11,824      11,586      18,282   —   55 58
Benzodiazepines 143,549 189,704 195,625 218,640 271,692    312,931    345,691    357,836 149   —
Alprazolam   46,528   57,419   65,236   80,313 104,762    112,552    124,902    123,744 166   —
Clonazepam   28,178   30,648   33,557   40,920   48,385      57,633      62,811      61,219 117   —
Diazepam   15,619   18,433   19,936   19,674   26,518      25,150      26,860      24,118   —   —
Lorazepam   17,674   23,210   23,720   26,213   36,602      36,582      36,675      42,874 143   —
Diphenhydramine   10,457   10,298   12,302   12,540   13,531      13,321      14,082      19,012   82   —
Hydroxyzine     2,363     2,179     2,679     2,447      5,647        3,690        5,902        4,978   —   —
Zolpidem   12,792   14,730   17,257   18,464   28,262      29,127      31,994      30,149 136   —
Cardiovascular agents   27,397   36,804   36,250   35,494   41,430      45,857      43,602      47,699   74   —
ACE inhibitors     3,542     6,361     5,064     6,860     8,146        8,075        7,813        6,980   97   —
Alpha agonists, central     3,616     5,125     4,810     4,751     6,197        5,258        5,742        9,080 151   —
Beta blockers     7,094     9,824   11,729   11,668   13,000      16,204      16,925      14,585 106   —
Calcium channel blocking agents     3,115     5,435     5,227     4,493     5,857        6,428        6,894        7,043   —   —
Diuretics     3,626     5,332     5,102     5,465     4,812        7,555        7,965        7,829   —   —
Central nervous system stimulants     9,979   11,519   14,276   18,794   18,879      21,997      28,491      40,648 307   85 43
Amphetamine-dextroamphetamine     2,303     2,669     5,027     6,372     6,500        8,656      11,327      17,272 650 100 52
Caffeine     2,736     4,567     4,508     2,165     1,876        2,074        2,712        1,848   —   —
Methylphenidate     2,446     2,519     2,192     4,782     3,173        4,953        4,089        4,918   —   —
Gastrointestinal agents     9,351     7,301   10,549   11,056   13,281      14,828      13,549      13,060   —   —
Hormones     5,203     6,897     7,868     8,036     7,846      10,424        9,373      12,539 141   —
Metabolic agents   11,343   21,014   23,416   27,097   25,422      31,204      34,507      27,794 145   —
Muscle relaxants   25,934   33,695   38,918   40,769   54,151      50,878      53,708      46,269   78   —
Carisoprodol   14,736   20,082   24,505   27,128   34,155      29,980      29,864      25,528   —   —
Cyclobenzaprine     6,183     7,629     7,142     6,197   12,748      11,178      12,411      11,551   87   —
Nutritional products     4,921     5,569     4,861     6,765     6,133        7,784      11,532      11,090 125   —
Pain relievers 241,584 294,258 323,665 363,720 458,451    516,409    567,524    573,497 137   —
Acetaminophen products   39,167   43,558   44,314   43,872   49,986      52,995      47,176      39,783   — −25
Aspirin products     9,580   12,123   10,399     9,726   13,007      13,930      12,979      11,074   —   —
Nonsteroidal anti-inflammatories   27,362   28,837   27,693   30,822   30,345      35,571      33,975      33,034   —   —
Ibuprofen   22,127   22,268   20,541   20,892   23,539      27,339      25,392      22,663   — −17
Naproxen     4,715     5,190     6,682     7,208     4,528        6,236        6,223        7,223   —   —
Opiates/opioids 172,738 217,600 247,669 286,618 366,823    416,814    474,133    488,004 183   —
Narcotic pain relievers 144,655 168,379 201,280 237,239 305,892    342,983    359,921    366,181 153   —
Buprenorphine products            *            *     4,440     7,136   12,544      14,266      15,778      21,483   —   51
Codeine products     7,176     6,181     6,928     5,648     8,235        7,962        7,928        9,927   —   —
Fentanyl products     9,823   11,211   16,012   15,947   20,179      20,945      21,196      20,034 104   —
Hydrocodone products   39,846   47,194   57,550   65,734   89,052      86,258      95,972      82,480 107   — −14 
Hydromorphone products     3,385     4,714     6,780     9,497   12,142      14,337      17,666      18,224 438   —
Methadone   36,806   42,684   45,130   53,950   63,629      63,031      65,945      66,870   82   —
Morphine products   14,090   15,762   20,416   29,591   28,818      31,731      29,605      34,593 146   —
Oxycodone products   41,701   52,943   64,891   76,684 105,526    148,974    146,355    151,218 263   —
Propoxyphene products     6,744     7,648     6,220     7,401   13,364        9,526        8,832        1,655 −75 −83 −81 
Opiates/opioids, unspecified   31,864   52,673   50,978   52,997   66,585      84,144    124,249    138,130 334   64
Tramadol products     4,849     5,918     6,048     8,039   11,850      15,349      16,251      20,000 312   —
Psychotherapeutic agents   91,268 101,451 112,856 119,787 124,331    132,483    131,698    135,455   —   —
Antidepressants   66,917   67,051   79,682   82,009   80,881      89,075      88,919      88,965   —   —
SSRI antidepressants   32,285   30,374   35,370   37,446   39,780      39,814      38,366      41,257   —   —
Tricyclic antidepressants   12,412   14,515   16,564   16,600   13,246      18,303      15,240      15,307   —   —
Antipsychotics   35,198   44,396   44,733   52,752   55,005      58,018      57,199      61,951   76   —
Respiratory agents   22,310   28,332   28,967   31,225   31,508      36,424      34,629      41,377   85   —
Antihistamines     5,761     4,429     4,130     5,096     8,282        9,439        8,617        8,441   —   —
Bronchodilators     2,294     3,043     2,920     3,043     3,046        3,123        4,386        3,762   —   —
Expectorants        832     1,966     2,125     2,293     2,089        4,172        3,035        5,336 541   — 76
Upper respiratory products   10,333   15,850   15,127   16,791   14,910      15,627      14,998      17,726   —   —

Large increases in the number of ED visits involving nonmedical use of pharmaceuticals were observed between 2004 and 2011. It is likely that there are multiple causes contributing to these increases. Some portion may be associated with the greater number of prescriptions being written, making prescription drugs more accessible and able to be diverted. Also, as more people are taking prescription medications as part of their regular health care, there is more risk that drugs taken as prescribed will interact with other drugs that are being used nonmedically. It is beyond the scope of this report to explore the causes behind the growing numbers of ED visits involving misuse or abuse of pharmaceuticals, and further research is needed.

Medical emergencies related to nonmedical use of pharmaceuticals increased 132 percent in the period from 2004 to 2011, rising from about a half million visits to about 1.25 million visits. Contributing heavily to this rise was a 183 percent increase in the involvement of drugs classified as opiates/opioids. There were over 315,000 more visits involving opiates/opioids in 2011 than in 2004. Narcotic pain relievers increased 153 percent, or over 220,000 visits, beyond the 2004 level of about 145,000 visits. Among specific opiate drugs, oxycodone had the largest impact, with a 263 percent increase and over 100,000 more visits in 2011 than in 2004. Drugs experiencing large relative increases but having smaller impact included tramadol (e.g., Ultram®), a narcotic-like opiate agonist used for moderate to severe pain, and hydromorphone (e.g., Dilaudid®), a morphine derivative. Visits involving tramadol increased 312 percent, reaching 20,000 visits in 2010. Hydromorphone involvement rose 438 percent, reaching almost 20,000 visits in 2011. For about a quarter of visits designated as involving opiates/opioids, the type of opiate involved was not reported in the ED records. The category "Opiates/opioids unspecified" rose 334 percent, with over 100,000 more visits in 2011 than in 2004.

Between 2004 and 2011, the number of visits involving drugs for anxiety and insomnia increased 138 percent overall—a jump of more than 244,000 visits over the 2004 level of about 180,000 visits. Benzodiazepines (e.g., alprazolam, clonazepam, diazepam, lorazepam) increased 149 percent and were involved in about 215,000 more visits in 2011 than in 2004. Visits involving zolpidem (e.g., Ambien®), a sleeping aid with benzodiazepine-like properties, increased 136 percent, reaching over 30,000 visits in 2011.

Trends in the short term are quite different from those observed in the long term. Overall, visits involving nonmedical use of pharmaceuticals increased just 15 percent over the 2 years between 2009 and 2011, about half the annual rate of increase seen in earlier years. There was no increase in overall opioid/opiates involvement in the short term. Among specific drugs, there were no measureable increases in visits involving the narcotic pain relievers codeine, fentanyl, hydromorphone, methadone, morphine, or oxycodone; propoxyphene involvement dropped from a high of over 13,000 visits in 2008 to under 2,000 visits in 2011 (88%);18 and hydrocodone involvement dropped 14 percent, or over 13,000 visits in the 1 year between 2010 and 2011. The most notable exception was for the category "Opiates/opioids unspecified," which increased 64 percent, or over 50,000 visits, between 2009 and 2011. The other exception is buprenorphine products, whose involvement increased by a little over 7,000 visits between 2009 and 2011 (51%). This trend likely reflects the increased availability of buprenorphine after the U.S. Food and Drug Administration approved its use for treatment of opioid dependence in 2002 and also the increasing number of physicians who subsequently became certified to prescribe it.19 In 2005, approximately 100,000 patients had received a buprenorphine prescription. By 2010, more than 800,000 patients had received a prescription—an eightfold increase.20

With one exception, there have been no short-term increases in the involvement of drugs for anxiety and insomnia between 2009 and 2011. The exception is barbiturates, whose involvement increased by a little under 7,000 visits between 2010 and 2011.

One category of drugs that has experienced both short- and long-term increases in involvement is CNS stimulants (e.g., ADHD drugs). With over 40,000 visits in 2011, visits with CNS stimulant involvement increased 307 percent in the long term and 85 percent in the short term. Among specific CNS stimulants, the ADHD drug amphetamine-dextroamphetamine (e.g., Adderall®) saw a 650 percent increase in the long term and 100 percent increase in the short term, for a total of over 17,000 visits in 2011. This growth in involvement of CNS stimulants echoes the previously noted short-term rise in illicit stimulants, where amphetamines/methamphetamine saw a 71% increase and a rise of over 66,000 visits between 2009 and 2011.

6. DRUG-RELATED SUICIDE ATTEMPTS

6.1 ED Visits Involving Drug-Related Suicide Attempts, 2011

According to the National Vital Statistics System, there were 38,285 suicide deaths in 2011 in the United States.21 Suicide was the second leading cause of death for adults aged 15 to 24 and the fourth leading cause for those aged 5 to 14 and 25 to 44.22 Substance abuse is strongly associated with suicide attempts. Evidence suggests that one third of those who died by suicide were positive for alcohol at the time of death and that nearly one in five had evidence of opiates in their system.23 Highlighting the relevance of drugs to the overall problem of life-threatening suicide attempts, the National Center for Injury Prevention and Control estimated that, overall, there were about 420,000 ED visits per year for the past 5 years resulting from self-harm; for the same range of years, DAWN estimated there were about 210,000 ED visits for suicide attempts involving drugs per year, or about half the total number of all visits for self-harm.24

DAWN data provide a unique window to study life-threatening suicide attempts that involve drugs in respect to the types of drugs involved, the characteristics of the patients, and the follow-up treatments provided. DAWN reports on suicide attempts involving all types of illicit drugs and prescription drugs as well as over-the-counter products and attempts involving alcohol alone for patients aged 20 or younger. DAWN cases are not limited to drug overdoses. Suicide attempts involving firearms, for example, are included as DAWN cases if drugs are noted as being involved at the time of the suicide attempt.25

DAWN estimated there were 228,366 ED visits resulting from drug-related suicide attempts in 2011 (Table 22). Almost all (94.7%) involved a prescription drug or over-the-counter medication, about two thirds (64.4%) involved multiple drugs, and over one quarter (29.0%) involved alcohol.

Table 22. ED visits involving drug-related suicide attempts, by selected drugs, 2011
Drug category and selected drugs (1) ED visits Percent
of ED
visits
RSE (%) 95% CI:
Lower
bound
95% CI:
Upper
bound
(1) The classification of drugs used in DAWN is derived from the Multum Lexicon, © 2012 Lexi-Comp, Inc. and/or Cerner Multum, Inc. The classification was modified to meet DAWN's unique requirements (2011). The Multum Licensing Agreement governing use of the Lexicon can be found on the DAWN Web site at http://www.samhsa.gov/data/dawn/MultumLicenseAgreement.pdf.
(2) Estimates of ED visits are based on a representative sample of general, non-Federal, short-stay hospitals in the United States with 24-hour EDs.
(3) ED visits often involve multiple drugs. Such visits will appear multiple times in this table (e.g., a visit involving both cocaine and marijuana will appear twice in this table). The sum of visits by drug will be greater than the total, and the sum of percentages by drug will be greater than 100.
NOTE: CI = confidence interval. RSE = relative standard error.
SOURCE: Center for Behavioral Health Statistics and Quality, SAMHSA, Drug Abuse Warning Network, 2011.
Total ED visits, suicide attempts (2,3) 228,366 100.0   6.8 197,745 258,986
Single drug   81,280   35.6   7.3   69,660   92,899
Multiple drugs 147,086   64.4   8.3 123,136 171,037
Alcohol present   66,186   29.0 10.3   52,760   79,612
Illicit drugs   33,826   14.8 15.5   23,564   44,089
Cocaine   14,442     6.3 18.9     9,080   19,803
Heroin     6,794     3.0 18.4     4,347     9,240
Marijuana   15,615     6.8 18.6     9,937   21,293
Amphetamines/methamphetamine     4,837     2.1 34.0     1,618     8,056
Pharmaceuticals 216,149   94.7   6.9 187,004 245,293
Anticonvulsants   15,419     6.8   9.4   12,585   18,252
Antidepressants   44,669   19.6   9.6   36,223   53,115
SSRI antidepressants   22,402     9.8 10.5   17,796   27,008
Citalopram     7,411     3.2 18.6     4,715   10,108
Fluoxetine     5,148     2.3 23.1     2,819     7,477
Paroxetine     1,074     0.5 30.3        437     1,710
Sertraline     5,644     2.5 27.2     2,637     8,652
Trazodone   10,919     4.8 15.1     7,683   14,155
Antipsychotics   29,345   12.9 14.1   21,243   37,448
Atypical antipsychotics   25,120   11.0 14.7   17,898   32,343
Quetiapine   16,413     7.2 15.8   11,341   21,484
Risperidone     2,867     1.3 20.4     1,718     4,016
Lithium     2,383     1.0 36.5        677     4,090
Anxiolytics, sedatives, hypnotics   93,271   40.8   7.2   80,034 106,508
Barbiturates     1,805     0.8 39.6        405     3,205
Benzodiazepines   66,807   29.3   8.1   56,252   77,362
Alprazolam   25,252   11.1 10.7   19,932   30,572
Clonazepam   21,793     9.5 13.7   15,923   27,662
Diazepam     6,004     2.6 20.7     3,563     8,444
Lorazepam   12,044     5.3 17.3     7,960   16,128
Diphenhydramine     9,301     4.1 14.9     6,587   12,014
Hydroxyzine     4,481     2.0 18.4     2,861     6,102
Zolpidem   14,764     6.5 16.3   10,044   19,484
Cardiovascular agents   14,759     6.5 14.5   10,561   18,958
ACE inhibitors     4,209     1.9 22.3     2,416     6,165
Alpha agonists, central     1,139     0.5 39.2        264     2,014
Beta blockers     5,345     2.3 16.4     3,624     7,065
Central nervous system stimulants (e.g., ADHD drugs)     4,715     2.1 19.0     2,959     6,471
Gastrointestinal agents     4,881     2.1 22.2     2,758     7,005
Hormones     2,524     1.1 22.2     1,426     3,622
Metabolic agents     4,399     1.9 18.5     2,804     5,993
Antidiabetic agents     3,263     1.4 27.1     1,530     4,996
Muscle relaxants   10,892     4.8 16.3     7,419   14,365
Carisoprodol     2,325     1.0 29.0     1,004     3,645
Cyclobenzaprine     5,676     2.5 19.2     3,538     7,815
Pain relievers   86,667   38.0   9.0   71,307 102,028
Acetaminophen products   29,822   13.1 14.1   21,584   38,060
Aspirin products     5,681     2.5 16.4     3,855     7,506
Narcotic pain relievers   31,697   13.9 10.9   24,943   38,451
Codeine products     2,495     1.1 27.8     1,137     3,852
Hydrocodone products   12,190     5.3 18.2     7,838   16,543
Methadone     2,060     0.9 36.4        589     3,530
Morphine products     2,043     0.9 23.6     1,099     2,988
Oxycodone products   13,806     6.0 15.1     9,719   17,893
Nonsteroidal anti-inflammatories (NSAIDs)   22,377     9.8 15.9   15,422   29,333
Tramadol products     5,692     2.5 25.9     2,804     8,580
Respiratory agents   12,204     5.3   9.6     9,907   14,501
Antihistamines     4,011     1.8 15.9     2,764     5,258
Upper respiratory products     6,142     2.7 18.1     3,962     8,322

Less than a fifth (14.8%) involved illicit drugs. Marijuana and cocaine were the more commonly involved illicit drugs, appearing in 6.8 and 6.3 percent of visits, respectively.

Pharmaceuticals were much more common than illicit drugs in suicide attempts:

After population size and sampling error are taken into account, the rate of drug-related suicide-attempt visits for females (84.7 visits per 100,000 population) was higher than that for males (61.5 visits) (Table 23, Figure 7). Suggesting the vulnerability of youth, rates ranged from a low of 12.0 visits per 100,000 population for those aged 65 or older to a high of 150.6 visits for those aged 18 to 20.

Table 23. ED visits involving drug-related suicide attempts, by patient demographics, 2011
Patient demographics ED visits Percent of ED
visits
Rate of ED visits
per 100,000
population (1)
(1) All rates are ED visits per 100,000 population. Population estimates are drawn from the set of United States Resident Population Estimates by Age, Sex, Race, and Hispanic Origin (Vintage 2011) issued by the U.S. Census Bureau.
(2) Estimates of ED visits are based on a representative sample of general, non-Federal, short-stay hospitals in the United States with 24-hour EDs.
NOTE: An asterisk (*) indicates that an estimate with a relative standard error greater than 50%, or an estimate based on fewer than 30 visits, has been suppressed. A dash (—) indicates a blank cell. Rates are not provided for race and ethnicity subgroups because of data limitations.
SOURCE: Center for Behavioral Health Statistics and Quality, SAMHSA, Drug Abuse Warning Network, 2011.
Total ED visits, suicide attempts (2) 228,366 100.0   73.3
Sex          —      —      —
Male   94,305   41.3   61.5
Female 134,046   58.7   84.7
Unknown            *        *        *
Age          —      —      —
0–5 years            *        *        *
6–11 years            *        *        *
12–17 years   23,005   10.1   91.6
18–20 years   20,341     8.9 150.6
21–24 years   24,605   10.8 140.1
25–29 years   30,122   13.2 141.6
30–34 years   25,687   11.2 125.2
35–44 years   40,784   17.9 100.4
45–54 years   42,027   18.4   94.0
55–64 years   16,748     7.3   44.0
65 years and older     4,953     2.2   12.0
Unknown            *        *        *
Race/ethnicity          —      —      —
White 154,620   67.7      —
Black   31,800   13.9      —
Hispanic   20,423     8.9      —
Other or two or more race/ethnicities     4,803     2.1      —
Unknown   16,720     7.3      —

Figure 7. Rates of ED visits per 100,000 population involving drug-related suicide attempts, by age and sex, 2011

Figure 7     D

SOURCE: Center for Behavioral Health Statistics and Quality, SAMHSA, Drug Abuse Warning Network, 2011.

Considering race/ethnicity, 67.7 percent of the suicide attempts involved patients who were White, 13.9 percent who were Black, 8.9 percent who were Hispanic, 2.1 percent who were of other or multiple race/ethnic groups, and 7.3 percent who were of unknown race/ethnicity. DAWN does not produce population-based rates for race/ethnicity categories because race/ethnicity information is often missing from ED records.

Overall, 81.7 percent of patients attempting drug-related suicide had some form of follow-up (Table 24).

Table 24. ED visits involving drug-related suicide attempts, by patient disposition, 2011
Patient disposition ED visits Percent of ED visits Rate of ED visits
per 100,000
population (1)
(1) All rates are ED visits per 100,000 population. Population estimates are drawn from the set of United States Resident Population Estimates by Age, Sex, Race, and Hispanic Origin (Vintage 2011) issued by the U.S. Census Bureau.
(2) Estimates of ED visits are based on a representative sample of general, non-Federal, short-stay hospitals in the United States with 24-hour EDs.
NOTE: An asterisk (*) indicates that an estimate with a relative standard error greater than 50%, or an estimate based on fewer than 30 visits, has been suppressed.
SOURCE: Center for Behavioral Health Statistics and Quality, SAMHSA, Drug Abuse Warning Network, 2011.
Total ED visits, suicide attempts (2) 228,366 100.0 73.3
Treated and released   52,469   23.0 16.8
Discharged home   33,625   14.7 10.8
Released to police/jail     2,772     1.2   0.9
Referred to detox/treatment            *        *      *
Admitted to this hospital 112,655   49.3 36.2
ICU/critical care   41,725   18.3 13.4
Surgery            *        *      *
Chemical dependency/detox            *        *      *
Psychiatric unit   20,464     9.0   6.6
Other inpatient unit   50,309   22.0 16.1
Other disposition   63,241   27.7 20.3
Transferred   57,938   25.4 18.6
Left against medical advice            *        *      *
Died            *        *      *
Other     2,465     1.1   0.8
Not documented     1,260     0.6   0.4

The remaining 18.3 percent of patients were either treated and discharged to home (14.7%) or had other outcomes.

The level of follow-up for drug-related suicides is approximately double that found for visits involving illicit drugs or nonmedical use of pharmaceuticals.

DAWN only records death as the outcome if the patient died in the ED after admission. DAWN does not record deaths for patients who died prior to admission to the ED or after admission to inpatient units of the hospital or transfer to another facility. Therefore, death as an ED disposition is rarely observed by DAWN.

6.2 Trends in ED Visits Involving Drug-Related Suicide Attempts, 2004–2011

This section presents the trends in the estimates of drug-related ED visits involving suicide attempts for the period from 2004 through 2011. Differences between years are presented in terms of the percentage increase or decrease in visits in 2011 compared with the estimates for 2004 (long-term trends) and for 2009 and 2010 (short-term trends). Only statistically significant changes are discussed and displayed in the tables.

With about 230,000 visits in 2011, the number of drug-related suicide attempts has risen 41 percent from 2004 to 2011 (Table 25).

Table 25. Trends in ED visits for drug-related suicide attempts, by selected drugs, 2004–2011
Drug category and selected drugs (1) ED visits,
2004
ED visits,
2005
ED visits,
2006
ED visits,
2007
ED visits,
2008
ED visits,
2009
ED visits,
2010
ED visits,
2011
Percent
change,
2004,
2011 (2)
Percent
change,
2009,
2011 (2)
Percent
change,
2010,
2011 (2)
(1) The classification of drugs used in DAWN is derived from the Multum Lexicon, © 2012 Lexi-Comp, Inc. and/or Cerner Multum, Inc. The classification was modified to meet DAWN's unique requirements (2011). The Multum Licensing Agreement governing use of the Lexicon can be found on the DAWN Web site at http://www.samhsa.gov/data/dawn/MultumLicenseAgreement.pdf.
(2) This column denotes statistically significant (p < 0.05) increases or decreases between estimates for the periods shown.
(3) Estimates of ED visits are based on a representative sample of general, non-Federal, short-stay hospitals in the United States with 24-hour EDs.
(4) ED visits often involve multiple drugs. Such visits will appear multiple times in this table (e.g., a visit involving both cocaine and marijuana will appear twice in this table). The sum of visits by drug will be greater than the total, and the sum of percentages by drug will be greater than 100.
NOTE: An asterisk (*) indicates that an estimate with a relative standard error greater than 50%, or an estimate based on fewer than 30 visits, has been suppressed. A dash (—) indicates a blank cell.
SOURCE: Center for Behavioral Health Statistics and Quality, SAMHSA, Drug Abuse Warning Network, 2011.
Total ED visits, suicide attempts (3,4) 161,586 151,568 182,805 197,053 199,469 198,403 212,736 228,366   41      
Illicit drugs   34,767   33,787   42,169   37,355   36,735   35,685   37,382   33,826   —   —   —
Cocaine   19,520   19,628   26,510   26,462   19,614   17,969   15,721   14,442   —   —   —
Heroin     4,579     3,167     4,265     4,444     4,249     5,019     6,017     6,794   —   —   —
Marijuana   12,074   11,955   15,272   12,115   17,285   14,176   17,219   15,615   —   —   —
Amphetamines/methamphetamine     4,535     5,411     4,829     2,665     2,788     3,429     3,573     4,837   —   —   —
Pharmaceuticals 145,496 138,447 169,040 185,270 188,644 186,883 201,519 216,149   49      
Anticonvulsants   10,957     9,391   12,580   11,803   14,486   13,299   14,318   15,419   —   —   —
Antidepressants   33,366   27,086   36,677   38,870   40,985   36,154   42,276   44,669   —   24   —
SSRI antidepressants   18,513   13,377   16,973   18,884   19,988   17,548   22,365   22,402   —   —   —
Citalopram     2,115        886     3,047     3,358     3,563     3,810     5,114     7,411 250   95   —
Fluoxetine     3,477     3,292     3,923     3,790     5,730     5,307     4,680     5,148   —   —   —
Paroxetine     4,509     2,927     2,054     2,071     2,013     1,777     2,563     1,074 −76   — −58
Sertraline     4,852     4,109     4,263     5,413     4,197     4,526     5,890     5,644   —   —   —
Trazodone     6,995     6,635     9,021     8,014     9,594     8,298   10,870   10,919   —   —   —
Antipsychotics   17,807   17,129   22,491   25,479   25,451   23,910   28,618   29,345   65   —   —
Atypical antipsychotics   15,016   14,300   19,429   20,250   21,228   20,499   23,507   25,120   67   —   —
Quetiapine     8,308     8,649   10,756   14,051   13,522   12,219   13,776   16,413   98   34   —
Risperidone     3,255     2,036     2,536     2,367     2,309     2,014     3,464     2,867   —   —   —
Lithium     1,832     1,281     1,298     2,751     2,948     2,663     3,830     2,383   —   —   —
Anxiolytics, sedatives, and hypnotics   52,657   52,022   68,181   72,639   78,995   77,623   80,750   93,271   77   —   —
Barbiturates     1,948     1,219     2,031     1,663     1,480     1,605        452     1,805   —   —   —
Benzodiazepines   36,995   35,676   50,431   53,509   55,823   56,851   60,318   66,807   81   —   —
Alprazolam   11,354   14,530   15,633   19,167   21,220   23,250   22,473   25,252 122   —   —
Clonazepam     9,402     9,064   14,173   14,455   14,571   16,060   20,033   21,793 132   —   —
Diazepam     4,630     3,968     5,909     6,912     5,313     6,120     6,236     6,004   —   —   —
Lorazepam     6,065     5,182     6,682     9,527     9,973     9,897   10,605   12,044   99   —   —
Diphenhydramine     7,461     6,583     7,760     7,620     8,414     8,384     7,195     9,301   —   —   —
Hydroxyzine     2,346     1,795     1,956     2,027     3,310     2,843     2,714     4,481   91   —   65
Zolpidem     4,355     4,972     6,674     7,405     9,533   10,815   11,092   14,764 239   —   —
Cardiovascular agents     7,667     5,814     7,952     7,850   12,592   10,413   14,227   14,759   93   42   —
ACE inhibitors     1,325     1,045     1,048     1,654     2,822     2,261     3,847     4,290 224   —   —
Alpha agonists, central        995        912     1,929        790     1,715     1,204     2,317     1,139   —   —   —
Beta blockers     2,105     1,916     1,999     2,501     5,094     3,829     3,571     5,345 154   —   —
Central nervous system stimulants (e.g., ADHD drugs)     1,659     2,086     1,959     2,288     3,270     3,446     4,407     4,715 184   —   —
Gastrointestinal agents     2,276     2,542     2,236     2,010     3,612     3,040     3,643     4,881   —   —   —
Hormones     1,124        533     1,573     2,016     2,161     2,024     2,359     2,524   —   —   —
Metabolic agents     2,145     3,048     3,720     2,252     3,181     4,918     5,312     4,399 105   —   —
Antidiabetic agents     1,841     2,580     2,941     1,438     2,749     3,602     3,505     3,263   —   —   —
Muscle relaxants     5,921     5,785     7,072     9,772     8,053     8,350   11,210   10,892   84   —   —
Carisoprodol     1,864     2,038     3,811     4,301     3,452     2,516     4,158     2,325   —   —   —
Cyclobenzaprine     2,966     2,784     2,096     3,839     3,438     3,955     4,621     5,676   91   —   —
Pain relievers   61,099   54,860   67,625   78,950   74,598   75,547   78,830   86,667   —   —   —
Acetaminophen products   20,703   21,019   25,312   29,864   26,406   24,072   28,747   29,822   —   —   —
Aspirin products     6,211     4,645     5,403     5,980     5,480     6,892     4,861     5,681   —   —   —
Narcotic pain relievers   16,930   17,803   24,470   29,886   26,817   29,595   32,987   31,697   87   —   —
Codeine products     1,752     2,656     2,349     1,637     2,315     1,512     2,433     2,495   —   —   —
Hydrocodone products     7,034     7,035     8,998   13,238   11,676   13,701   12,863   12,190   —   —   —
Methadone     1,287     1,596     1,772     3,192     2,008     2,474     1,651     2,060   —   —   —
Morphine products        714     1,210            *     1,690     1,161     1,423     2,343     2,043   —   —   —
Oxycodone products     5,342     4,229     7,842     9,351     8,760   10,945   13,199   13,806 158   —   —
Nonsteroidal anti-inflammatories (NSAIDs)   19,116   14,117   15,956   18,810   18,658   19,127   18,603   22,377   —   —   —
Tramadol     1,742     1,515     1,719     2,816     3,057     2,305     2,669     5,692 227 147 113
Respiratory agents     8,363     7,747     8,426   10,205     9,166     7,943   10,636   12,204   —   54   —
Antihistamines     2,059     1,650     1,627     3,813     2,979     2,475     3,369     4,011   —   —   —
Upper respiratory products     4,820     4,289     3,982     4,078     4,642     3,167     4,249     6,142   —   —   —

7. SEEKING DETOX SERVICES

7.1 ED Visits Involving Seeking Detox Services, 2011

The DAWN category of visits referred to as "seeking detox" includes nonemergency requests for admission for detoxification and visits to obtain medical clearance before entry to a detox program as well as acute emergencies in which an individual is experiencing withdrawal symptoms and seeking detox.26 Because detox may be sought through other avenues (e.g., direct admission to a hospital, services provided through private clinics, entry into programs outside the community), the overall demand for detox services is most likely higher than suggested by DAWN estimates.

DAWN estimates that there were 250,596 drug-related ED visits for patients seeking detox or substance abuse treatment services during 2011 (Table 26). Visits for almost three quarters (66.4%) of patients seeking detox involved multiple drugs. On average, 27.9 percent of visits associated with seeking detox involved alcohol.27 Approximately 60 percent of visits involved illicit drugs and 60 percent involved pharmaceuticals. Cocaine was observed in 24.2 percent of visits, heroin in 31.5 percent, marijuana in 14.5 percent, and amphetamines/methamphetamine in 6.6 percent. Other illicit drugs were seen at lower levels. Among pharmaceuticals, narcotic pain relievers were observed in 37.6 percent of visits, including oxycodone at 17.1 percent. Benzodiazepines (anti-anxiety drugs) were observed in 21.8 percent of visits, with alprazolam (e.g., Xanax) at 12.0 percent accounting for about half.

Table 26. ED visits involving seeking detox services, by selected drugs, 2011
Drug category and selected drugs (1) ED
visits
Percent
of ED
visits
RSE (%) 95% CI:
Lower
bound
95% CI:
Upper
bound
(1) The classification of drugs used in DAWN is derived from the Multum Lexicon, © 2012 Lexi-Comp, Inc. and/or Cerner Multum, Inc. The classification was modified to meet DAWN's unique requirements (2011). The Multum Licensing Agreement governing use of the Lexicon can be found on the DAWN Web site at http://www.samhsa.gov/data/dawn/MultumLicenseAgreement.pdf.
(2) Estimates of ED visits are based on a representative sample of general, non-Federal, short-stay hospitals in the United States with 24-hour EDs.
(3) ED visits often involve multiple drugs. Such visits will appear multiple times in this table (e.g., a visit involving both cocaine and marijuana will appear twice in this table). The sum of visits by drug will be greater than the total, and the sum of percentages by drug will be greater than 100.
NOTE: CI = confidence interval. RSE = relative standard error.
SOURCE: Center for Behavioral Health Statistics and Quality, SAMHSA, Drug Abuse Warning Network, 2011.
Total ED visits, seeking detox (2,3) 250,596 100.0 29.3 106,830 394,363
Single drug   84,250   33.6 29.0   36,351 132,149
Multiple drugs 166,346   66.4 29.7   69,405 263,287
Alcohol involved   69,850   27.9 15.9   48,115   91,584
Illicit drugs 147,297   58.8 18.7   93,246 201,348
Cocaine   60,609   24.2 19.7   37,150   84,069
Heroin   78,931   31.5 18.1   50,999 106,862
Marijuana   36,277   14.5 18.5   23,120   49,434
Amphetamines/methamphetamine   16,566     6.6 34.9     5,241   27,892
PCP     4,582     1.8 30.5     1,839     7,326
Pharmaceuticals 158,905   63.4   40.9   31,445 286,365
Antidepressants        966     0.4 43.6        140     1,793
Anxiolytics, sedatives, and hypnotics   56,393   22.5 36.9   15,618   97,169
Benzodiazepines   54,532   21.8 37.3   14,715   94,348
Alprazolam   30,172   12.0 41.7     5,513   54,832
Central nervous system stimulants (e.g., ADHD drugs)     2,272     0.9 47.6        151     4,394
Muscle relaxants     2,988     1.2 41.5        557     5,419
Pain relievers 121,000   48.3 47.7     7,796 234,205
Opiates/opioids 117,571   46.9 48.2     6,389 228,753
Narcotic pain relievers   94,118   37.6 46.7     7,954 180,282
Buprenorphine products     7,364     2.9 29.1     3,161   11,568
Morphine products     5,970     2.4 43.5        877   11,064
Oxycodone products   42,808   17.1 33.2   14,937   70,679
Respiratory agents     1,864     0.7 35.5        568     3,160

When population size and sampling error are taken into account, the rate of seeking detox visits for males (98.8 per 100,000 population) was higher than that for females (62.6 per 100,000 population) (Table 27, Figure 8). Rates of seeking detox visits were over 100 visits per 100,000 population for those aged 18 to 44, peaking at 257.4 for those aged 21 to 24.

Table 27. ED visits involving seeking detox services, by patient demographics, 2011
Patient demographics ED visits Percent of ED visits Rate of ED visits
per 100,000
population (1)
(1) All rates are ED visits per 100,000 population. Population estimates are drawn from the set of United States Resident Population Estimates by Age, Sex, Race, and Hispanic Origin (Vintage 2011) issued by the U.S. Census Bureau.
(2) Estimates of ED visits are based on a representative sample of general, non-Federal, short-stay hospitals in the United States with 24-hour EDs.
NOTE: An asterisk (*) indicates that an estimate with a relative standard error greater than 50%, or an estimate based on fewer than 30 visits, has been suppressed. A dash (—) indicates a blank cell. Rates are not provided for race and ethnicity subgroups because of data limitations.
SOURCE: Center for Behavioral Health Statistics and Quality, SAMHSA, Drug Abuse Warning Network, 2011.
Total ED visits, seeking detox (2) 250,596 100.0   80.4
Sex          —      —      —
Male 151,487   60.5   98.8
Female   99,105   39.5   62.6
Unknown            *        *        *
Age          —      —      —
0–5 years            *        *        *
6–11 years            *        *        *
12–17 years            *        *        *
18–20 years   17,917     7.1 132.6
21–24 years   45,195   18.0 257.4
25–29 years   46,179   18.4 217.0
30–34 years   40,794   16.3 198.9
35–44 years   43,343   17.3 106.7
45–54 years   39,708   15.8   88.8
55–64 years   12,303     4.9   32.3
65 years and older     2,228     0.9     5.4
Unknown            *        *        *
Race/ethnicity          —      —      —
White 193,495   77.2      —
Black   31,468   12.6      —
Hispanic   11,672     4.7      —
Other or two or more race/ethnicities     1,555     0.6      —
Unknown   12,406     5.0      —

Figure 8. Rates of ED visits per 100,000 population involving seeking detox services, by age and sex, 2011

Figure 8     D

SOURCE: Center for Behavioral Health Statistics and Quality, SAMHSA, Drug Abuse Warning Network, 2011.

In terms of race/ethnicity, the majority (77.2%) of seeking detox visits involved patients who were White, 12.6 percent who were Black, and 4.7 percent who were Hispanic. DAWN does not produce population-based rates for race/ethnicity categories because race/ethnicity information is often missing in ED records.

Nearly 60 percent (57.4%) of ED patients classified as seeking detox obtained some follow-up based on their ED visit: 30.4 percent were admitted to the hospital, 20.1 percent were referred to detox/treatment services, and 6.9 percent were transferred to another facility (Table 28). The remaining patients were treated and discharged home (38.5%) or had other outcomes (4.1%).

Table 28. ED visits involving seeking detox services, by patient disposition, 2011
Patient disposition ED visits Percent of ED visits Rate of ED visits
per 100,000
population (1)
(1) All rates are ED visits per 100,000 population. Population estimates are drawn from the set of United States Resident Population Estimates by Age, Sex, Race, and Hispanic Origin (Vintage 2011) issued by the U.S. Census Bureau.
(2) Estimates of ED visits are based on a representative sample of general, non-Federal, short-stay hospitals in the United States with 24-hour EDs.
NOTE: An asterisk (*) indicates that an estimate with a relative standard error greater than 50%, or an estimate based on fewer than 30 visits, has been suppressed.
SOURCE: Center for Behavioral Health Statistics and Quality, SAMHSA, Drug Abuse Warning Network, 2011.
Total ED visits, seeking detox (2) 250,596 100.0 80.4
Treated and released 147,148   58.7 47.2
Discharged home   96,465   38.5 31.0
Released to police/jail        275     0.1   0.1
Referred to detox/treatment   50,408   20.1 16.2
Admitted to this hospital   76,136   30.4 24.4
ICU/critical care     1,408     0.6   0.5
Surgery            *        *      *
Chemical dependency/detox   34,541   13.8 11.1
Psychiatric unit   14,452     5.8   4.6
Other inpatient unit            *        *      *
Other disposition   27,311   10.9   8.8
Transferred   17,263     6.9   5.5
Left against medical advice     3,925     1.6   1.3
Died            *        *      *
Other     3,120     1.2   1.0
Not documented            *        *      *

7.2 Trends in ED Visits Involving Seeking Detox Services, 2004–2011

This section presents the trends in the estimates of ED visits involving seeking detox services for the period from 2004 through 2011 (Table 29). Differences between years are presented in terms of the percentage increase or decrease in visits in 2011 compared with the estimates for 2004 (long-term trends) and for 2009 and 2010 (short-term trends). Only statistically significant changes are discussed and displayed in the table.

Table 29. Trends in ED visits involving seeking detox services, by selected drugs, 2004–2011
Drug category and selected drugs (1) ED visits,
2004
ED visits,
2005
ED visits,
2006
ED visits,
2007
ED visits,
2008
ED visits,
2009
ED visits,
2010
ED visits,
2011
Percent
change,
2004,
2011 (2)
Percent
change,
2009,
2011 (2)
Percent
change,
2010,
2011 (2)
(1) The classification of drugs used in DAWN is derived from the Multum Lexicon, © 2012 Lexi-Comp, Inc. and/or Cerner Multum, Inc. The classification was modified to meet DAWN's unique requirements (2011). The Multum Licensing Agreement governing use of the Lexicon can be found on the DAWN Web site at http://www.samhsa.gov/data/dawn/MultumLicenseAgreement.pdf.
(2) This column denotes statistically significant (p < 0.05) increases or decreases between estimates for the periods shown.
(3) Estimates of ED visits are based on a representative sample of general, non-Federal, short-stay hospitals in the United States with 24-hour EDs.
(4) ED visits often involve multiple drugs. Such visits will appear multiple times in this table (e.g., a visit involving both cocaine and marijuana will appear twice in this table). The sum of visits by drug will be greater than the total, and the sum of percentages by drug will be greater than 100.
NOTE: An asterisk (*) indicates that an estimate with a relative standard error greater than 50%, or an estimate based on fewer than 30 visits, has been suppressed. A dash (—) indicates a blank cell.
SOURCE: Center for Behavioral Health Statistics and Quality, SAMHSA, Drug Abuse Warning Network, 2011.
Total ED visits, seeking detox (3,4) 141,867 126,226 118,355 139,908 177,879 205,407 232,542 250,596         
Illicit drugs 110,798 101,250   92,387 106,662 124,375 131,163 141,837 147,297         
Cocaine   62,989   56,061   57,738   65,124   68,824   60,076   64,211   60,609   —   —   —
Heroin   47,035   40,895   34,464   42,242   51,932   58,233   62,078   78,931   —   36   —
Marijuana   25,965   22,486   22,104   25,970   32,887   37,513   43,040   36,277   —   —   —
Amphetamines/methamphetamine   11,760   15,402     8,128     7,161   12,418   11,085   13,633   16,566   —   —   —
PCP        827        729        989            *     1,478     1,134     1,309     4,582 454 304 250
Pharmaceuticals   48,646   44,727   44,457   59,660   94,949 123,080 150,505 158,905         
Antidepressants     1,024     1,195     1,141     1,314     1,894     1,769     1,410        966   —   —   —
Anxiolytics, sedatives, and hypnotics   15,748   16,533   16,799   20,365   42,178   49,768   55,482   56,393   —   —   —
Benzodiazepines   14,717   15,734   15,801   19,301   41,576   48,769   53,830   54,532   —   —   —
Alprazolam     6,061     6,253     7,063     9,138            *   27,647   28,396   30,172   —   —   —
Central nervous system stimulants (e.g., ADHD drugs)            *        829        589     1,049            *     1,994     1,288     2,272   —   —   —
Muscle relaxants     1,356     1,204     1,214     1,701     1,381     2,332     2,192     2,988   —   —   —
Pain relievers   34,730   30,114   31,797   42,785   69,604   90,381 121,456 121,000   —   —   —
Opiates/opioids   33,296   29,330   30,893   41,250   65,632   87,670 118,527 117,571   —   —   —
Narcotic pain relievers   29,894   25,550   26,987   37,049   58,491   78,426 105,684   94,118   —   —   —
Buprenorphine products            *            *            *            *            *     4,858     7,372     7,364   —   —   —
Morphine products     1,638     2,399     3,002     3,341     5,066     3,597     6,134     5,970   —   —   —
Oxycodone products   15,917   14,028   14,831   18,905   34,306   45,591   67,079   42,808   —   — −36
Respiratory agents            *            *            *            *        348            *     1,215     1,864   —   —   —

While ED visits by patients seeking detox for illicit drugs did not change significantly either in the long or short term, a short-term increase of 36 percent between 2009 and 2011 was observed for heroin, with over 20,000 more visits in 2011 than in 2009. Pharmaceutical involvement in ED visits seeking detox has also been stable, with the exception of a 1-year spike in oxycodone. Between 2009 and 2010, involvement of oxycodone rose 47 percent but then dropped 36 percent between 2010 and 2011, returning to its 2009 level.28

8. ADVERSE REACTIONS TO PHARMACEUTICALS

8.1 ED Visits Involving Adverse Reactions to Pharmaceuticals, 2011

Adverse reactions to pharmaceuticals are a growing problem in the United States. It is likely that there are multiple causes contributing to increases in adverse reactions. Some portion may be associated with the greater number of prescriptions being written and more people taking prescription drugs as part of their medical care. Additionally, people of all ages are increasingly being prescribed multiple drugs simultaneously, which, in turn, increases the possibility for unintended interactions. This is particularly common among older populations who are placed on long-term medication for chronic conditions, and the number of older persons in the nation is growing.29 While it is beyond the scope of this report to assess the precise impact of these different causes, DAWN data provide insight concerning the number and characteristics of medical emergencies resulting from the recent use of prescription drugs, over-the-counter pharmaceuticals, or other therapeutic substances used as prescribed or indicated. Included in DAWN are ED visits related to side effects, drug-drug interactions, and drug-alcohol interactions. Visits involving illicit drug abuse or documented misuse of pharmaceuticals are excluded from this grouping.30

As with all ED visits that DAWN considers to be drug related, the involvement of a drug must be documented in the ED records. If the relationship between a drug and an adverse reaction is not recognized, a visit will not be considered drug related and will not be captured by DAWN. Also, adverse reactions that are identified in different medical settings (e.g., during a visit to the doctor's office or while a patient is already hospitalized) will not be captured by DAWN. Therefore, the total number of people experiencing adverse drug reactions is greater than reported by DAWN.

For 2011, DAWN estimates that 2,301,059 ED visits (Table 30), or 738.5 visits per 100,000 population (Table 31), involved adverse reactions to prescription medicines, over-the-counter drugs, or other types of pharmaceuticals. This represents just under half (45.4%) of all drug-related ED visits. About one in five (17.6%) involved multiple drugs. Alcohol was a contributing factor in just 1.3 percent of adverse reaction visits.

Table 30. ED visits involving adverse reaction to pharmaceuticals, 2011
Drug category and selected drugs (1) ED visits Percent
of ED
visits
RSE
(%)
95% CI:
Lower
bound
95% CI:
Upper
bound
(1) The classification of drugs used in DAWN is derived from the Multum Lexicon, © 2012 Lexi-Comp, Inc. and/or Cerner Multum, Inc. The classification was modified to meet DAWN's unique requirements (2011). The Multum Licensing Agreement governing use of the Lexicon can be found on the DAWN Web site at http://www.samhsa.gov/data/dawn/MultumLicenseAgreement.pdf.
(2) Estimates of ED visits are based on a representative sample of general, non-Federal, short-stay hospitals in the United States with 24-hour EDs.
(3) ED visits often involve multiple drugs. Such visits will appear multiple times in this table (e.g., a visit involving both penicillin and tramadol will appear twice in this table). The sum of visits by drug will be greater than the total, and the sum of percentages by drug will be greater than 100.
NOTE: CI = confidence interval. RSE = relative standard error.
SOURCE: Center for Behavioral Health Statistics and Quality, SAMHSA, Drug Abuse Warning Network, 2011.
Total ED visits, adverse reaction (2,3) 2,301,059 100.0   6.2 2,021,724 2,580,394
Single drug 1,895,436   82.4   6.2 1,665,903 2,124,968
Multiple drugs    405,623   17.6 10.0    326,273    484,973
Alcohol present      30,635     1.3 12.3      23,247      38,022
Pharmaceuticals 2,300,827 100.0   6.2 2,021,473 2,580,180
Anticoagulants    130,567     5.7   8.6    108,470    152,665
Anticonvulsants      88,301     3.8   9.0      72,718    103,884
Antidepressants    102,471     4.5   9.3      83,858    121,085
Antidiabetic agents    126,030     5.5 11.5      97,526    154,534
Anti-infectives    517,750   22.5   7.1    445,752    589,749
Cephalosporins      58,116     2.5   9.5      47,291      68,941
Macrolide derivatives      41,034     1.8   9.1      33,723      48,346
Penicillins    139,289     6.1   8.4    116,296    162,282
Quinolones      64,032     2.8   9.7      51,859      76,204
Sulfonamides      90,294     3.9   6.9      78,078    102,510
Antineoplastics (chemotherapy drugs)    135,319     5.9 18.8      85,429    185,208
Antipsychotics      79,219     3.4   7.7      67,208      91,229
Anxiolytics, sedatives, and hypnotics      99,135     4.3   9.7      80,363    117,907
Benzodiazepines      57,559     2.5 13.1      42,726      72,393
Zolpidem      15,570     0.7 15.9      10,717      20,423
Cardiovascular agents    214,868     9.3 11.5    166,281    263,454
ACE inhibitors      65,959     2.9 12.6      49,717      82,201
Beta blockers      45,597     2.0 12.2      34,684      56,509
Calcium channel blocking agents      31,479     1.4 21.4      18,246      44,713
Diuretics      36,548     1.6   8.9      30,167      42,930
Gastrointestinal agents      79,683     3.5 14.1      57,610    101,757
Laxatives      27,354     1.2 17.2      18,136      36,573
Herbal and nutraceutical products (alternative medicines)      16,656     0.7 13.8      12,149      21,163
Hormones    129,909     5.6   8.8    107,383    152,435
Adrenal cortical steroids      51,674     2.2 13.2      38,327      65,021
Sex hormones      37,403     1.6 13.6      27,416      47,390
Immunologic agents      98,307     4.3 10.9      77,386    119,228
Viral vaccines      33,204     1.4 13.9      24,178      42,230
Muscle relaxants      27,355     1.2 12.0      20,925      33,784
Nutritional products      79,638     3.5   9.2      65,307      93,968
Pain relievers    362,192   15.7   8.1    304,501    419,884
Acetaminophen products      20,543     0.9 14.7      14,631      26,456
Aspirin products      34,432     1.5 13.5      25,327      43,537
Narcotic pain relievers    190,252     8.3   9.2    155,780    224,724
Hydrocodone products      74,631     3.2   9.7      60,389      88,872
Oxycodone products      65,012     2.8 14.2      46,970      83,054
Nonsteroidal anti-inflammatories (NSAIDs)      75,322     3.3 10.4      59,976      90,668
Tramadol products      27,421     1.2 13.2      20,328      34,514
Radiologic agents      20,773     0.9 14.5      14,872      26,673
Respiratory agents      85,947     3.7   8.5      71,693    100,201
Topical agents      70,360     3.1   9.2      57,623      83,097
Table 31. ED visits and rates involving adverse reaction to pharmaceuticals, by patient demographics, 2011
Patient demographics ED visits Percent of ED
visits
Rate of ED visits
per 100,000
population (1)
(1) All rates are ED visits per 100,000 population. Population estimates are drawn from the set of United States Resident Population Estimates by Age, Sex, Race, and Hispanic Origin (Vintage 2011) issued by the U.S. Census Bureau.
(2) Estimates of ED visits are based on a representative sample of general, non-Federal, short-stay hospitals in the United States with 24-hour EDs.
NOTE: An asterisk (*) indicates that an estimate with a relative standard error greater than 50%, or an estimate based on fewer than 30 visits, has been suppressed. A dash (—) indicates a blank cell. Rates are not provided for race and ethnicity subgroups because of data limitations.
SOURCE: Center for Behavioral Health Statistics and Quality, SAMHSA, Drug Abuse Warning Network, 2011.
Total ED visits, adverse reaction (2) 2,301,059 100.0    738.5
Sex             —      —         —
Male    895,584   38.9    584.2
Female 1,404,571   61.0    887.3
Unknown               *        *         —
Age             —      —         —
0–5 years    204,279     8.9    842.4
6–11 years      60,990     2.7    248.2
12–17 years      80,946     3.5    322.4
18–20 years      74,304     3.2    550.1
21–24 years    112,676     4.9    641.7
25–29 years    138,190     6.0    649.4
30–34 years    133,077     5.8    648.8
35–44 years    260,261   11.3    640.6
45–54 years    300,744   13.1    672.5
55–64 years    303,592   13.2    797.6
65 years and older    631,611   27.4 1,525.8
Unknown               *        *         —
Race/ethnicity             —      —         —
White 1,509,366   65.6         —
Black    314,937   13.7         —
Hispanic    250,439   10.9         —
Other or two or more race/ethnicities      51,755     2.2         —
Unknown    174,563     7.6         —

With reference to the specific types of drugs involved, adverse reactions show a very different pattern from nonmedical use of pharmaceuticals in that visits involve a much wider array of drugs. Not surprisingly, given their widespread use, anti-infectives (e.g., antibiotics) were found to be involved in 22.5 percent of adverse reaction visits. Of these, penicillins were involved in 6.1 percent of adverse reaction visits, followed by sulfonamides (e.g., sulfa drugs) in 3.9 percent, quinolones (e.g., Cipro®) in 2.8 percent, cephalosporins (e.g., Keflex®) in 2.5 percent, and macrolides (e.g., Zithromax®) in 1.8 percent.

Pain relievers were found to be involved in 15.7 percent of visits. Among these, 8.3 percent involved narcotic pain relievers, 3.3 percent involved nonsteroidal anti-inflammatories (NSAIDs), 1.5 percent involved aspirin products, and under 1.0 percent involved acetaminophen products.

Cardiovascular agents were found to be involved in 9.3 percent of visits. Among these, angiotensin-converting enzyme (ACE) inhibitors (e.g., Prinivil®, Zestril®) were involved in 2.9 percent and beta blockers (e.g., Lopressor®, Toprol XL®) in 2.0 percent.

Appearing in between 5 and 6 percent of visits each were anticoagulants (e.g., Coumadin®), antidiabetic agents (e.g., insulin), and antineoplastics (chemotherapy drugs).

Appearing in between 3 and 5 percent of visits each were antidepressants, antipsychotics, and anxiolytics (drugs used to treat insomnia and anxiety).

When population size and sampling error were taken into account, women had notably more visits than men (887.3 and 584.2 visits per 100,000 population, respectively; Table 31, Figure 9). For children aged 5 and under, the rate of ED visits for adverse reactions was 842.4 visits per 100,000 population. The rate dropped to a low of 248.2 visits for children aged 6 to 11 and then rose consistently to reach a high of 1,525.8 visits for patients aged 65 or older.

Figure 9. Rates of ED visits per 100,000 population involving adverse reaction to pharmaceuticals, by age and sex, 2011

Figure 9     D

SOURCE: Center for Behavioral Health Statistics and Quality, SAMHSA, Drug Abuse Warning Network, 2011.

In terms of race/ethnicity, 65.6 percent of visits related to adverse reaction to pharmaceuticals involved patients who were White, 13.7 percent who were Black, and 10.9 percent who were Hispanic. DAWN does not produce population-based rates for race/ethnicity categories because race/ethnicity information is often missing from ED records.

About three quarters (76.6%) of patients were treated and released (Table 32). About a fifth (20.6%) of patients were admitted to the hospital, and the remainder (2.8%) had other outcomes.

Table 32. ED visits and rates involving adverse reaction to pharmaceuticals, by patient disposition, 2011
Patient disposition ED visits Percent of ED
visits
Rate of ED visits
per 100,000
population (1)
(1) All rates are ED visits per 100,000 population. Population estimates are drawn from the set of United States Resident Population Estimates by Age, Sex, Race, and Hispanic Origin (Vintage 2011) issued by the U.S. Census Bureau.
(2) Estimates of ED visits are based on a representative sample of general, non-Federal, short-stay hospitals in the United States with 24-hour EDs.
NOTE: An asterisk (*) indicates that an estimate with a relative standard error greater than 50%, or an estimate based on fewer than 30 visits, has been suppressed.
SOURCE: Center for Behavioral Health Statistics and Quality, SAMHSA, Drug Abuse Warning Network, 2011.
Total ED visits, adverse reaction (2) 2,301,059 100.0 738.5
Treated and released 1,762,091   76.6 565.5
Discharged home 1,754,690   76.3 563.1
Released to police/jail        4,436     0.2     1.4
Referred to detox/treatment               *        *        *
Admitted to this hospital    474,999   20.6 152.4
ICU/critical care      38,980     1.7   12.5
Surgery               *        *        *
Chemical dependency/detox               *        *        *
Psychiatric unit        6,828     0.3     2.2
Other inpatient unit    425,531   18.5 136.6
Other disposition      63,968     2.8   20.5
Transferred      29,092     1.3     9.3
Left against medical advice      12,150     0.5     3.9
Died               *        *        *
Other      10,687     0.5     3.4
Not documented               *        *        *

8.2 Trends in ED Visits Involving Adverse Reaction to Pharmaceuticals, 2005–2011

This section presents the trends in the estimates of ED visits involving adverse reactions for the period from 2005 through 2011 (Table 33). Differences between years are presented in terms of the percentage increase or decrease in visits in 2011 compared with the estimates for 2005 (long-term trends) and for 2009 and 2010 (short-term trends).31 Only statistically significant changes are discussed and displayed in the table.

Table 33. Trends in ED visits involving adverse reaction to pharmaceuticals, by selected drugs, 2005–2011
Drug category and selected drugs (1) ED visits,
2005
ED visits,
2006
ED visits,
2007
ED visits,
2008
ED visits,
2009
ED visits,
2010
ED visits,
2011
Percent
change,
2005,
2011 (2,3)
Percent
change,
2009,
2011 (2)
Percent
change,
2010,
2011 (2)
(1) The classification of drugs used in DAWN is derived from the Multum Lexicon, © 2012 Lexi-Comp, Inc. and/or Cerner Multum, Inc. The classification was modified to meet DAWN's unique requirements (2011). The Multum Licensing Agreement governing use of the Lexicon can be found on the DAWN Web site at http://www.samhsa.gov/data/dawn/MultumLicenseAgreement.pdf.
(2) This column denotes statistically significant (p < 0.05) increases or decreases between estimates for the periods shown.
(3) Due to data limitations in 2004, long-term trends for adverse reaction visits are assessed for the period from 2005 through 2011, not from 2004 through 2011.
(4) Estimates of ED visits are based on a representative sample of general, non-Federal, short-stay hospitals in the United States with 24-hour EDs.
(5) ED visits often involve multiple drugs. Such visits will appear multiple times in this table (e.g., a visit involving both penicillin and tramadol will appear twice in this table). The sum of visits by drug will be greater than the total, and the sum of percentages by drug will be greater than 100.
NOTE: A dash (—) indicates a blank cell.
SOURCE: Center for Behavioral Health Statistics and Quality, SAMHSA, Drug Abuse Warning Network, 2011.
Total ED visits, adverse reaction to pharmaceuticals (4,5) 1,250,377 1,526,010 1,908,928 2,157,128 2,287,271 2,329,221 2,301,059   84      
Anticoagulants    108,180    125,687    167,929    189,577    194,696    157,911    130,567   — −33 −17
Anticonvulsants      44,281      59,924      73,256      83,018      86,835      81,954      88,301   99   —   —
Antidepressants      46,702      65,458      76,222      84,604      91,396    102,397    102,471 119   —   —
Antidiabetic agents      77,625    115,513    166,006    136,971    140,067    145,534    126,030   —   —   —
Anti-infectives    306,110    367,088    426,442    487,757    477,221    506,358    517,750   69   —   —
Cephalosporins      38,442      44,794      48,713      53,648      52,408      54,007      58,116   —   —   —
Macrolide derivatives      39,981      42,982      42,478      47,074      48,960      50,656      41,034   — −16 −19
Penicillins      97,308    104,693    122,912    134,340    128,283    136,714    139,289   —   —   —
Quinolones      46,791      59,683      65,308      76,114      67,151      69,521      64,032   —   —   —
Sulfonamides      36,879      47,657      59,681      75,391      75,905      85,907      90,294 145   —   —
Antineoplastics (chemotherapy drugs)      48,569      51,273      70,618      94,810    105,199    124,591    135,319 179   —   —
Antipsychotics      40,330      55,941      65,818      75,531      79,002      84,842      79,219   96   —   —
Anxiolytics, sedatives, and hypnotics      49,044      57,467      79,269    100,702    104,404    102,401      99,135 102   —   —
Benzodiazepines      25,520      33,482      48,129      61,880      63,494      59,055      57,559 126   —   —
Zolpidem        6,111        6,680      12,417      16,188      19,951      19,487      15,570 155 −22   —
Cardiovascular agents    116,037    169,629    207,270    237,663    247,063    241,637    214,868   85   —   —
ACE inhibitors      27,100      38,781      53,707      69,041      72,219      69,196      65,959 143    
Beta blockers      24,669      40,653      56,551      54,778      58,179      59,842      45,597   85 −22 −24
Calcium channel blocking agents      12,742      18,200      22,935      22,926      30,354      27,233      31,479 147   —   —
Diuretics      19,023      33,779      42,425      46,008      44,745      44,809      36,548   92   —   —
Gastrointestinal agents      36,238      50,487      62,307      72,801      82,951      81,295      79,683 120   —   —
Herbal and nutraceutical products
(alternative medicines)
       6,360        6,286        9,803      11,919      12,149      14,961      16,656 162   —   —
Hormones      49,979      70,790      89,729    104,174    114,714    123,718    129,909 160   —   —
Adrenal cortical steroids      29,506      37,292      44,431      44,756      49,403      52,753      51,674   75   —   —
Sex hormones      10,697      15,218      22,386      28,216      31,821      35,423      37,403 250   —   —
Immunologic agents      38,786      52,280      66,492      86,235    104,473    100,818      98,307 153   —   —
Viral vaccines      13,372      18,817      21,559      29,329      52,874      38,266      33,204 148 −37   —
Muscle relaxants      12,173      15,454      22,285      26,556      27,551      28,265      27,355 125   —   —
Nutritional products      26,885      38,349      44,519      63,607      67,182      77,056      79,638 196   —   —
Pain relievers    223,725    266,602    321,246    363,947    387,197    379,260    362,192   62   —   —
Acetaminophen products      15,498      17,033      20,485      17,469      22,997      26,178      20,543   —   —   —
Aspirin products      24,435      36,450      40,851      47,722      42,983      38,997      34,432   —   —   —
Narcotic pain relievers    116,677    139,021    174,720    198,891    218,366    207,322    190,252   63   —   —
Hydrocodone products      42,260      52,307      62,948      80,270      79,877      83,518      74,631   77   —   —
Oxycodone products      28,511      36,404      54,433      54,868      65,146      57,223      65,012 128   —   —
Nonsteroidal anti-inflammatories (NSAIDs)      55,755      61,262      72,250      70,867      70,035      79,248      75,322   —   —   —
Tramadol products      10,091      12,746      16,946      23,756      25,884      25,887      27,421 172   —   —
Radiologic agents      12,604      14,479      17,896      18,798      20,434      16,425      20,773   65   —   —
Respiratory agents      61,702      68,812      82,958      90,751      96,462      82,801      85,947   —   —   —
Topical agents      30,703      37,117      44,843      44,761      51,728      61,263      70,360 129   36   —

ED visits resulting from adverse reactions to pharmaceuticals increased 84 percent in the period from 2005 to 2011, rising from about 1.3 million visits to about 2.3 million visits. The number of ED visits for adverse reactions to pharmaceuticals rose by about a quarter million visits, or more, per year between 2005 and 2008, leveling off at about 2.3 million visits per year over the period from 2009 to 2011. Accordingly, most drugs, though not all, have seen some increase in involvement in the long term between 2005 and 2011 but, unless noted otherwise, no short-term increases. The following remarks are ordered by number of visits in 2011.

9. ACCIDENTAL INGESTION OF DRUGS

9.1 ED Visits Involving Accidental Ingestion of Drugs, 2011

To be classified by DAWN as an accidental ingestion ED visit, a drug must have been taken unintentionally or without it being known which drug was actually taken. The drug may be taken by the patient or given to the patient by someone else (e.g., a parent giving medication to a child).32

This chapter focuses on the characteristics of accidental ingestion ED visits for children aged 5 and under as the preponderance of ED visits for accidental ingestion involve children in this age range. In 2011, DAWN found 77,074 ED visits out of a total of 113,624 involved children aged 5 and under. The rate of these ED visits was about 25 times higher for children aged 5 and under than for adults: 317.8 visits per 100,000 children aged 5 and under compared with 12.9 visits per 100,000 for the general adult population aged 21 or older (Figure 10). As soon as infants learn to crawl and especially once they learn to walk, their mobility, curiosity, and tendency to put things in their mouths make many substances in the home a potential danger.33 Pharmaceutical products belonging to other household members present a particularly critical danger to children because, due to their physiology and smaller size, children's unintended ingestions of even small amounts can lead to medical emergencies requiring care in an ED.34 This combination of propensity, accessibility, and susceptibility is evidenced in calls to poison control centers, where over half (51.0%) of human exposure calls involve children aged 5 and under and where 14 of the top 25 substances involved in pediatric exposure are drugs and therapeutic substances.35

Figure 10. Rates of ED visits per 100,000 population involving accidental ingestion of pharmaceuticals, by age, 2011

Figure 10     D

SOURCE: Center for Behavioral Health Statistics and Quality, SAMHSA, Drug Abuse Warning Network, 2011.

Drugs recognized as being particularly dangerous when accidentally ingested by children include pain medications, such as narcotic pain relievers (e.g., oxycodone, hydrocodone); cardiac medications, such as calcium channel blockers ("heart pills") and blood pressure medicines (e.g., clonidine); aspirin products; antidepressants (e.g., Elavil®, Wellbutrin®, Zyban®); antidiabetic medications; camphor-containing salves (when ingested); eye drops (e.g., Clear Eyes®); and nasal sprays (e.g., Afrin®).36

Considering only these particularly dangerous drugs, DAWN found the following:

Table 34. ED visits involving accidental ingestion of drugs by patients aged 5 and under, 2011
Drug category and selected drugs (1) ED visits Percent of
ED visits
RSE (%) 95% CI:
Lower
bound
95% CI:
Upper
bound
(1) The classification of drugs used in DAWN is derived from the Multum Lexicon, © 2012 Lexi-Comp, Inc. and/or Cerner Multum, Inc. The classification was modified to meet DAWN's unique requirements (2011). The Multum Licensing Agreement governing use of the Lexicon can be found on the DAWN Web site at http://www.samhsa.gov/data/dawn/MultumLicenseAgreement.pdf.
(2) Estimates of ED visits are based on a representative sample of general, non-Federal, short-stay hospitals in the United States with 24-hour EDs.
(3) ED visits often involve multiple drugs. Such visits will appear multiple times in this table (e.g., a visit involving both aspirin and antihistamines will appear twice in this table). The sum of visits by drug will be greater than the total, and the sum of percentages by drug will be greater than 100.
NOTE: CI = confidence interval. RSE = relative standard error. An asterisk (*) indicates that an estimate with an RSE greater than 50%, or an estimate based on fewer than 30 visits, has been suppressed.
SOURCE: Center for Behavioral Health Statistics and Quality, SAMHSA, Drug Abuse Warning Network, 2011.
Total ED visits, accidental ingestion (2,3) 77,074 100.0 11.8 59,237 94,912
Pharmaceuticals 76,638   99.4 11.9 58,807 94,469
Anticonvulsants   2,571     3.3 22.6   1,433   3,710
Antidepressants   4,291     5.6 25.6   2,134   6,448
Antidiabetic agents   1,813     2.4 39.1      423   3,202
Antihyperlipidemic agents   1,175     1.5 48.7        53   2,296
Anti-infectives   2,612     3.4 38.6      637   4,588
Antipsychotics   2,413     3.1 35.9      715   4,111
Anxiolytics, sedatives, and hypnotics   8,479   11.0 20.2   5,117 11,841
Benzodiazepines   2,556     3.3 24.2   1,342   3,771
Diphenhydramine   4,311     5.6 28.0   1,947   6,676
Cardiovascular agents   9,398   12.2 24.5   4,887 13,909
ACE inhibitors   1,771     2.3 41.4      336   3,206
Beta blockers   1,934     2.5 30.6      774   3,093
Blood pressure drugs   1,234     1.6 42.2      213   2,254
Calcium channel blocking agents   2,884     3.7 48.1      166   5,602
Central nervous system stimulants (e.g., ADHD drugs)   3,952     5.1 30.8   1,564   6,340
Amphetamine-dextroamphetamine   2,179     2.8 45.1      253   4,105
Gastrointestinal agents   4,180     5.4 28.3   1,865   6,496
Hormones   2,145     2.8 17.2   1,422   2,868
Nutritional products   1,638     2.1 31.0      644   2,632
Pain relievers 18,971   24.6 12.7 14,231 23,710
Acetaminophen products   6,935     9.0 22.1   3,926   9,944
Aspirin products   1,592     2.1 36.4      457   2,727
Narcotic pain relievers   5,187     6.7 29.4   2,199   8,175
Nonsteroidal anti-inflammatories (NSAIDs)   4,876     6.3 22.8   2,702   7,051
Respiratory agents   5,980     7.8 19.5   3,697   8,262
Topical agents   7,604     9.9 19.0   4,776 10,432

Other drugs found at measureable levels included the following:

A negligible number of visits involved alcohol or illicit drugs.

Overall, there were 317.8 ED visits per 100,000 persons aged 0 to 5 resulting from accidental ingestion of drugs or other therapeutic substances (Table 35). The Consumer Product Safety Commission's National Electronic Injury Surveillance System (NEISS) reported a similar rate of 336.1 drug poisoning injuries treated in an ED per 100,000 population aged 0 to 4.37

Table 35. ED visits and rates involving accidental ingestion of drugs by patients aged 5 and under, by patient demographics, 2011
Patient demographics ED visits Percent of ED
visits
Rate of ED visits
per 100,000
population (1)
(1) All rates are ED visits per 100,000 population. Population estimates are drawn from the set of United States Resident Population Estimates by Age, Sex, Race, and Hispanic Origin (Vintage 2011) issued by the U.S. Census Bureau.
(2) Estimates of ED visits are based on a representative sample of non-Federal, short-stay hospitals with 24-hour EDs in the United States.
NOTE: An asterisk (*) indicates that an estimate with a relative standard error greater than 50%, or an estimate based on fewer than 30 visits, has been suppressed. A dash (—) indicates a blank cell. Rates are not provided for race and ethnicity subgroups because of data limitations.
SOURCE: Center for Behavioral Health Statistics and Quality, SAMHSA, Drug Abuse Warning Network, 2011.
Total ED visits, accidental ingestion (2) 77,074 100.0 317.8
Sex        —      —      —
Male 40,988   53.2 330.8
Female 36,085   46.8 304.2
Unknown          *        *      —
Age        —      —      —
0 year   6,276     8.1 157.0
1 year 25,018   32.5 630.3
2 year 27,001   35.0 679.8
3 year 12,143   15.8 296.0
4 year   4,000     5.2   97.0
5 year   2,636     3.4   64.5
Race/ethnicity        —      —      —
White 46,325   60.1      —
Black   8,307   10.8      —
Hispanic 14,166   18.4      —
Other or two or more race/ethnicities   1,460     1.9      —
Unknown   6,818     8.8      —

Among children aged 0 to 5, a preponderance (67.5%) of visits involved children aged 1 or 2, and the rates for children aged 1 and 2 were each over 600 visits per 100,000 persons of that age. No differences were found by sex. In terms of race/ethnicity, 60.1 percent of visits involved patients who were White, 10.8 percent who were Black, and 18.4 percent who were Hispanic. DAWN does not produce population-based rates for race/ethnicity categories because race/ethnicity information is often missing from ED records.

The large majority (87.6%) of patients aged 5 and under were treated and discharged home (Table 36). The balance received more extensive follow-up care, e.g., admission to the hospital (7.4%), transfer to another facility (3.6%).

Table 36. ED visits and rates involving accidental ingestion of drugs by patients aged 5 and under, by patient disposition, 2011
Patient disposition ED visits Percent of ED
visits
Rate of ED visits
per 100,000
population (1)
(1) All rates are ED visits per 100,000 population. Population estimates are drawn from the set of United States Resident Population Estimates by Age, Sex, Race, and Hispanic Origin (Vintage 2011) issued by the U.S. Census Bureau.
(2) Estimates of ED visits are based on a representative sample of non-Federal, short-stay hospitals with 24-hour EDs in the United States.
NOTE: An asterisk (*) indicates that an estimate with a relative standard error greater than 50%, or an estimate based on fewer than 30 visits, has been suppressed. A dash (—) indicates a blank cell.
SOURCE: Center for Behavioral Health Statistics and Quality, SAMHSA, Drug Abuse Warning Network, 2011.
Total ED visits, accidental ingestion (2) 77,074 100    317.8
Treated and released 67,529   87.6 278.5
Discharged home 67,529   87.6 278.5
Released to police/jail          *        *        *
Referred to detox/treatment          *        *        *
Admitted to this hospital   5,736     7.4   23.7
ICU/critical care   1,246     1.6     5.1
Surgery          *        *        *
Chemical dependency/detox          *        *        *
Psychiatric unit          *        *        *
Other inpatient unit   4,491     5.8   18.5
Other disposition   3,809     4.9   15.7
Transferred   2,766     3.6   11.4
Left against medical advice          *        *        *
Died          *        *        *
Other          *        *        *
Not documented          *        *      —

9.2 Trends in ED Visits Involving Accidental Ingestion of Drugs by Patients Aged 5 and Under, 2004–2011

This section presents the trends in the estimates of ED visits involving accidental ingestion of drugs by patients aged 5 and under for the period from 2004 through 2011 (Table 37). Differences between years are presented in terms of the percentage increase or decrease in visits in 2011 compared with the estimates for 2004 (long-term trends) and for 2009 and 2010 (short-term trends). Only statistically significant changes are discussed and displayed in the table.

Table 37. Trends in ED visits involving accidental ingestion of drugs by patients aged 5 and under, by selected drugs, 2004–2011
Drug category and selected drugs (1) ED visits,
2004
ED visits,
2005
ED visits,
2006
ED visits,
2007
ED visits,
2008
ED visits,
2009
ED visits,
2010
ED visits,
2011
Percent
change,
2004,
2011 (2)
Percent
change,
2009,
2011 (2)
Percent
change,
2010,
2011 (2)
(1) The classification of drugs used in DAWN is derived from the Multum Lexicon, © 2012 Lexi-Comp, Inc. and/or Cerner Multum, Inc. The classification was modified to meet DAWN's unique requirements (2011). The Multum Licensing Agreement governing use of the Lexicon can be found on the DAWN Web site at http://www.samhsa.gov/data/dawn/MultumLicenseAgreement.pdf.
(2) This column denotes statistically significant (p < 0.05) increases or decreases between estimates for the periods shown.
(3) Estimates of ED visits are based on a representative sample of general, non-Federal, short-stay hospitals in the United States with 24-hour EDs.
(4) ED visits often involve multiple drugs. Such visits will appear multiple times in this table (e.g., a visit involving both aspirin and antihistamines will appear twice in this table). The sum of visits by drug will be greater than the total, and the sum of percentages by drug will be greater than 100.
NOTE: An asterisk (*) indicates that an estimate with a relative standard error greater than 50%, or an estimate based on fewer than 30 visits, has been suppressed. A dash (—) indicates a blank cell.
SOURCE: Center for Behavioral Health Statistics and Quality, SAMHSA, Drug Abuse Warning Network, 2011.
Total ED visits, accidental ingestion (3,4) 50,503 44,663 57,422 65,408 69,121 62,696 73,115 77,074      
Pharmaceuticals 50,098 44,477 57,285 64,779 68,431 61,894 72,795 76,638      
Anticonvulsants   2,447   1,764      832      861   1,944   1,877   2,931   2,571   —   —
Antidepressants   2,845   3,838   5,351   3,227   4,287   3,646   4,709   4,291   —   —
Antidiabetic agents          *   2,060   1,414   2,343   2,705      785   1,850   1,813   —   —
Antihyperlipidemic agents          *      932      808          *      444   1,456      889   1,175   —   —
Anti-infectives   1,242      930   1,564   1,725   1,925   1,283   1,347   2,612   —   —
Antipsychotics   1,667   1,441   1,230   1,667   2,034   1,690   3,875   2,413   —   —
Anxiolytics, sedatives, and hypnotics   3,854   3,045   5,706   6,260   8,039   7,065   7,269   8,479 120   —
Benzodiazepines   1,870   1,424   3,041   3,361   5,325   3,688   3,932   2,556   — −35
Diphenhydramine   1,513      880   1,900   2,478   1,806   2,121   2,304   4,311   —   —
Cardiovascular agents   7,300   7,287   9,327 11,193 10,646   9,087   9,226   9,398   —   —
ACE inhibitors      834   1,057      886   1,245   3,028   1,629   1,461   1,771   —   —
Beta blockers   2,267   2,448   2,741   2,986   3,299   2,375   3,252   1,934   —   —
Blood pressure drugs      884   1,264   2,427   2,009   1,661      792   1,702   1,234   —   —
Calcium channel blocking agents   1,108      876      524   1,637   1,049   1,656      736   2,884   —   —
Central nervous system stimulants (e.g., ADHD drugs)   1,919      900   2,457   3,730   1,869   1,628   2,360   3,952   —   —
Gastrointestinal agents   2,423   2,105   2,349   2,950   3,300   2,261   3,186   4,180   —   —
Hormones      564   1,662   1,443   1,519   2,814   1,497   1,497   2,145 280   —
Nutritional products   2,660   2,187   2,177   4,835   2,333   2,888   3,335   1,638   —   —
Pain relievers 12,048   9,631 14,451 13,606 14,579 17,797 20,441 18,971   —   —
Acetaminophen products   6,198   4,760   5,915   5,523   7,010   8,348   7,709   6,935   —   —
Aspirin products      722      589   1,251   1,753      528      604   1,923   1,592   —   —
Narcotic pain relievers   1,596   1,866   2,798   2,434   2,679   4,755   5,113   5,187 225   —
Nonsteroidal anti-inflammatories (NSAIDs)   2,635   2,108   4,681   3,795   4,581   3,896   4,373   4,876   —   —
Respiratory agents   7,167   5,290   5,539 10,032   7,302   5,378   8,600   5,980   — −30
Topical agents   2,383   2,328   3,320   3,565   6,110   5,662   3,895   7,604 219   —

Medical emergencies related to accidental ingestions by patients aged 5 and under were stable from 2004 to 2011, though increases were observed for particular drug groups. With over 8,000 visits recorded in 2011, drugs to treat anxiety and insomnia rose 120 percent since 2004. With about 5,000 visits in 2011, narcotic pain relievers rose 225 percent over that period. Topical agents rose 219 percent, reaching over 7,000 visits in 2011. Hormone-containing drugs increased in the long term by 280 percent, reaching over 2,000 visits in 2011.

No increases were observed in the short term, and two drugs groups, benzodiazepines and respiratory agents, saw declines (35% and 30%, respectively) in the 1 year between 2010 and 2011. The decrease in benzodiazepine involvement appears to part of general decline that began in 2008. The decrease in respiratory agents merely offsets a 1-year spike that occurred between 2009 and 2010, returning visits to their 2009 level.

End Notes

1 DAWN documents can be found on the DAWN Web site at http://www.samhsa.gov/data/DAWN.aspx.
2 DAWN data can be found on the SAMHDA Web site at http://www.icpsr.umich.edu/icpsrweb/SAMHDA/studies/31264?q=DAWN.
3 The classification of drugs used in DAWN is derived from the Multum Lexicon, © 2012 Lexi-Comp, Inc. and/or Cerner Multum, Inc. The classification was modified to meet DAWN's unique requirements (2011). The Multum Licensing Agreement governing use of the Lexicon can be found on the DAWN Web site at http://www.samhsa.gov/data/dawn/MultumLicenseAgreement.pdf.
4 Population counts were drawn from the set of United States Resident Population Estimates by Age, Sex, Race, and Hispanic Origin (Vintage 2011) issued by the U.S. Census Bureau.
5 Due to data limitations in 2004, long-term comparisons for ED visits resulting from adverse reactions are made between 2005 and the current year.
6 Drugs that DAWN considers to be illicit yet have legitimate medicinal uses include amphetamines; ketamine; and anesthetic gases, such as nitrous oxide ("laughing gas"). DAWN Field Reporters are careful to distinguish abuse from adverse reactions when classifying visits involving these drugs.
7 Heroin-related ED visits may be slightly underestimated. When drugs related to an ED visit are determined through toxicology tests, heroin metabolites are indistinguishable from other opiates unless a test specifically for the heroin metabolite is conducted. In the absence of this test, or if there is no evidence in the written record that heroin, specifically, was involved, the visit will be grouped with pharmaceuticals labeled "unspecified opiates" and not classified as heroin, an illicit drug. The number of drug misuse or abuse ED visits involving unspecified opiates is estimated at 157,981 visits, and about 53 percent of these (84,499 visits) were determined through toxicology testing. The portion that is attributable to heroin is unknown.
8 European Monitoring Centre for Drugs and Drug Addiction (EMCDDA). (2009). Understanding the 'Spice' phenomenon (EMCDDA Thematic Paper). Luxembourg: Office for Official Publications of the European Communities. Retrieved May 5, 2012, from http://www.emcdda.europa.eu/publications/thematic-papers/spice.
9 National Institute on Drug Abuse (NIDA). (2012, May). DrugFacts: Spice (Synthetic marijuana). Retrieved May 5, 2012, from http://www.drugabuse.gov/publications/infofacts/spice.
10 Johnston, L. D., O'Malley, P. M., Bachman, J. G., & Schulenberg, J. E. (2011, December 14). Marijuana use continues to rise among U.S. teens, while alcohol use hits historic lows [Press release]. Ann Arbor, MI: University of Michigan News Service. Retrieved May 5, 2012, from http://www.monitoringthefuture.org.
11 See Glossary of DAWN Terms, 2011 Update, for additional information on synthetic cannabinoids and their reporting by DAWN.
12 National Institute on Alcohol Abuse and Alcoholism (NIAAA). (2008, July). Alcohol and other drugs. Retrieved June 22, 2012, from http://pubs.niaaa.nih.gov/publications/AA76/AA76.htm.
13 Office of National Drug Control Policy (ONDCP). (2011). A response to the epidemic of prescription drug abuse. Retrieved May 5, 2012, from http://www.whitehouse.gov/ondcp/ondcp-fact-sheets/response-to-the-epidemic-of-prescription-drug-abuse.
14 Substance Abuse and Mental Health Services Administration (SAMHSA). Results from the 2011 National Survey of Drug Use and Health: Summary of national findings, NSDUH Series H-44, HHS Publication No. (SMA) 12-4713. Rockville, MD. Retrieved December 27, 2012, from http://www.samhsa.gov/data/NSDUH/2k11Results/NSDUHresults2011.htm.
15 DAWN tries to capture only pharmaceuticals that are related to the ED visit and actively discourages reporting of current medications that are unrelated to the visit. Given the limitations of medical record documentation, though, it is not always possible to distinguish and exclude current medications that are unrelated to the visit. This limitation may have the effect of overstating the variety of pharmaceuticals involved in ED visits.
16 Multiple drugs may not all be taken for the same reason; a patient may misuse one type of prescription medication while taking another medication as prescribed. To be counted as a DAWN case involving multiple drugs, though, both drugs must be involved as a reason for the ED visit (e.g., the drugs' interaction caused or worsened the medical emergency).
17 ED records frequently do not distinguish methadone used properly for the treatment of opiate addiction (and not specifically related to the ED visit) from nonmedical methadone use (related to the ED visit). This could result in overreporting the estimated number of ED visits related to methadone, but the extent of the overreporting is unknown.
18 In November 2010, the U.S. Food and Drug Administration (FDA) issued a recommendation against continued prescribing and use of the pain reliever propoxyphene because new data showed that the drug may cause serious toxicity to the heart, even when used at therapeutic doses. FDA requested that companies voluntarily withdraw propoxyphene from the U.S. market. Propoxyphene is an opioid pain reliever used to treat mild-to-moderate pain. It is sold under various names as a single-ingredient product (e.g., Darvon®) and as part of a combination product with acetaminophen (e.g., Darvocet®).
19 Substance Abuse and Mental Health Services Administration (SAMHSA), Center for Behavioral Health Statistics and Quality (CBHSQ). (2013, January 29). The DAWN Report: Emergency department visits involving buprenorphine. Rockville, MD. Retrieved March 21, 2013, from http://www.samhsa.gov/data/2k13/DAWN106/sr106-buprenorphine.pdf.
20 Ibid.
21 Hoyert, D. L., & Xu, J. Q. (2012, October 10). Deaths: Preliminary data for 2011. National Vital Statistics Reports, 61(6), 4. Hyattsville, MD: National Center for Health Statistics. Retrieved December 28, 2012, from http://www.cdc.gov/nchs/data/nvsr/nvsr61/nvsr61_06.pdf.
22 Ibid, 29–30.
23 Centers for Disease Control and Prevention (CDC), National Center for Injury Prevention and Control (NCIPC). (2010, Summer). Suicide: Facts at a glance. Retrieved May 5, 2012, from http://www.cdc.gov/ViolencePrevention/pdf/Suicide-DataSheet-a.pdf.
24 Centers for Disease Control and Prevention (CDC), National Center for Injury Prevention and Control (NCIPC). WISQARS nonfatal injury query system, 2007–2011. Retrieved January 4, 2013, from http://webappa.cdc.gov/sasweb/ncipc/nfirates2001.html.
25 Excluded are suicide-related behaviors documented as something other than actual attempts (e.g., suicidal ideation, suicidal gestures, or suicidal thoughts).
26 Some detox programs, in the hospital or the community, require medical clearance before a person can be admitted to a program. Medical clearance establishes whether a person has any special medical needs (e.g., person is diabetic and needs insulin) or is not suitable to mingle with other patients in the program (e.g., person has an infectious disease or is mentally unstable).
27 The role of alcohol may be underrepresented here because, for patients aged 21 and older, DAWN captures alcohol use only when it is combined with the use of other drugs.
28 Substance Abuse and Mental Health Services Administration (SAMHSA). (2012). Drug Abuse Warning Network, 2010: National estimates of drug-related emergency department visits. HHS Publication No. (SMA) 12-4733, DAWN Series D-38. Rockville, MD.
29 Substance Abuse and Mental Health Services Administration (SAMHSA), Center for Behavioral Health Statistics and Quality (CBHSQ). (2011). The DAWN Report: Emergency department visits involving adverse reactions to medications among older adults. Rockville, MD. Retrieved March 22, 2013, from http://www.samhsa.gov/data/2k10/TDR013AdverseReactionsOlderAdults/AdverseReactionsOlderAdults_HTML.pdf.
30 While adverse reactions are typically limited to pharmaceuticals, a small number involve drugs classified as illicit by DAWN for which there are legitimate medicinal uses (e.g., nitrous oxide when used by a dentist for sedation; cocaine when used as a topical anesthetic for eye surgery).
31 Due to data limitations in 2004, long-term trends for adverse reaction visits are assessed for the period from 2005 through 2011 and not from 2004 through 2011.
32 A visit is not considered as resulting from accidental ingestion if a patient took too much of his or her own medications because he or she forgot having taken a dose earlier.
33 Ma, D. (2009). Keep curious kids safe by poison proofing your home. AAP News, 30(11), 2. Retrieved May 5, 2012, from http://aapnews.aappublications.org/content/30/11.
34 Centers for Disease Control and Prevention (CDC). (2006). Nonfatal, unintentional medication exposures among children—United States, 2001–2003. Morbidity and Mortality Weekly Report, 55(1), 1–5. Retrieved May 5, 2012, from http://www.cdc.gov/mmwr/preview/mmwrhtml/mm5501a1.htm.
35 Bronstein, A. C., Spyker, D. A., Cantilena, L. R., Jr., Green, J. L., Rumack, B. H., & Dart, R. C. (2011). 2010 Annual report of the American Association of Poison Control Centers' National Poison Data System (NPDS): 28th annual report. Clinical Toxicology, 49, 910–941. Retrieved December 18, 2012, from http://www.poison.org/stats/2010%20NPDS%20Annual%20Report.pdf.
36 Eldridge, D. L., Mutter, K. W., & Holstege, C. P. (2010). An evidence-based review of single pills and swallows that can kill a child. Pediatric Emergency Medicine Practice, 7(3).
37 U.S. Consumer Product Safety Commission (CPSC). (n.d.). NEISS 2011 data highlights. Retrieved March 21, 2013, from http://www.cpsc.gov/en/Research--Statistics/NEISS-Injury-Data/.



Attachment A

Glossary of DAWN Terms,
2011 Update

This glossary defines terms used in data collection activities, analyses, and publications associated with the emergency department (ED) component of the Drug Abuse Warning Network (DAWN). The glossary is updated to reflect terms and conventions applicable in the 2011 data collection year.

Accidental ingestion: This category of drug-related ED visits includes those involving the accidental ingestion of a drug, for example, childhood drug poisonings and individuals who take the wrong medication by mistake. It includes a caregiver administering the wrong medicine by mistake. It does not include a patient taking more medicine than directed because the patient forgot to take it earlier. (See Nonmedical use of pharmaceuticals, Overmedication.)

Adverse reaction: This category of drug-related ED visits represents the use of a prescription or over-the-counter pharmaceutical for therapeutic purposes that results in an ED visit due to adverse drug reactions, side effects, drug-drug interactions, and drug-alcohol interactions. Although adverse reactions are typically limited to pharmaceuticals, a small number of adverse reaction visits involve (a) illicit drugs for which there are legitimate pharmaceutical versions, and (b) pharmaceutical inhalants (such as anesthetic gases).

Alcohol use: DAWN notes whether alcohol was involved in addition to other drug(s) for patients of all ages. Because alcohol is considered an illicit drug for minors, alcohol without the involvement of other drugs is considered a drug-related ED visit for patients under the age of 21. (See Drug misuse or abuse and Underage drinking.)

Case description: A description of how the drug(s) were related to the patient's ED visit. The case description, in conjunction with other documentation in the ED medical record, is used to determine whether the ED visit is reportable to DAWN. It is copied verbatim from the patient's chart when possible.

Case type: See Type of case.

Case type other: See Drug misuse or abuse.

Confidence interval (CI): An interval estimate, that is, a range of values around a point estimate that takes sampling error into account. A broadly accepted standard of confidence is 95 percent. If repeated samples were drawn from the same population of hospitals using the same sampling and data collection procedures, the true population value would fall within the CI 95 percent of the time. A 95 percent CI is a straightforward way to summarizes both the estimate and its margin of error.

Diagnosis: The condition(s) for which the patient was treated as determined by the clinician after evaluation.

Disposition: The location or facility to which an ED patient was referred, transferred, or released.

Treated and released includes three categories:

Admitted to this hospital includes five categories of inpatient units:

Other disposition includes five categories:

Drug: A substance that is (a) used as a medication or in the preparation of medication; (b) an illicit substance that causes addiction, habituation, or a marked change in consciousness; or (c) both. Substances reportable to DAWN include alcohol; illicit drugs (e.g., club drugs, cocaine, heroin, marijuana, synthetic cannabinoids, amphetamines/methamphetamine); nonpharmaceutical inhalants; prescription drugs (e.g., drugs for attention deficit hyperactivity disorder, antibiotics, antidepressants, antipsychotics, anticoagulants, beta blockers, birth control pills, hormone replacement, insulin, muscle relaxants, pain relievers, sleeping aids); drugs used in treatment of medical conditions (e.g., respiratory therapy, chemotherapy, radiation therapy); vaccines; dietary supplements; vitamins; and other over-the-counter pharmaceutical products. DAWN publications use the term "drug" to refer to any of these substances. Multiple substances can be reported for each DAWN case. Therefore, the total number of drugs exceeds the total number of DAWN cases reported.

Drug category: A generic grouping of related pharmaceuticals or other substances reported to DAWN, based on the classification system developed by Multum Information Services, a subsidiary of the Cerner Corporation, and modified for use with DAWN. The Multum Lexicon is available at http://www.multum.com/. In general, the Multum drug categories reflect the therapeutic uses for prescription and over-the-counter pharmaceuticals.

Additional clarification is provided for the following drug categories, because these are unique to DAWN:

Drug misuse or abuse: A group of ED visits defined broadly to include all visits associated with illicit drugs, alcohol use in combination with other drugs, alcohol use alone among those younger than 21 years, and nonmedical use of pharmaceuticals. (See also Alcohol use, Illicit drug use, Nonmedical use of pharmaceuticals, and Underage drinking.)

Drug-related ED visit: This category includes any ED visit related to recent drug use. To be a DAWN case, the ED visit must have involved a drug, either as the direct cause of the visit or as a contributing factor. (See also Single-drug case.) One patient may make repeated visits to an ED or to several EDs, thus producing a number of visits. The number of unique patients involved in the reported drug-related ED visits cannot be estimated because no direct patient identifiers are collected by DAWN.

There are some circumstances in which ED visits are not reviewed for DAWN. These include persons who left before being seen by a physician, visits for suture removal, and direct admission to the hospital through the ED for women in labor.

Estimate: A statistical estimate is the value of a parameter (such as the number of drug-related ED visits) for the universe that is derived by applying sampling weights and other adjustments to data from a sample. Estimates of drug-related ED visits are calculated by applying weights and adjustments to the data provided by the sampled hospitals participating in DAWN. The sampling weights reflect the probability of selection; separate adjustment factors account for nonresponse, data quality, and the known total of ED visits delivered by the universe of eligible hospitals as identified by the American Hospital Association (AHA) Annual Survey Database (ASDB) for the relevant time period.

GHB: Gammahydroxybutyric acid, a hallucinogen and depressant frequently combined with alcohol and other beverages. Also used by bodybuilders to aid in fat reduction and muscle building. For further information, see http://www.drugabuse.gov/infofacts/infofactsindex.html.

Hospital emergency department (ED): An emergency department (ED) (also known as an emergency room) is a medical treatment facility, specializing in acute care of patients who present without prior appointment, either by their own means or by ambulance. EDs are usually found in hospitals or other primary care centers. Only EDs in hospitals that meet DAWN's eligibility criteria may participate in DAWN. For information on drug-related ED visits, DAWN relies exclusively on medical records maintained by EDs. No patients, ED staff, or other records are consulted. DAWN is based on a sample of hospitals; in the cases where there are multiple EDs in a hospital, records from all the EDs are reviewed to identify drug-related cases. (See Universe.)

Illicit drug use: This category of drug-related ED visits includes all visits related to the use of illicit or illegal drugs. Illicit drugs include

Additional clarification is provided for the following drug categories:

LSD: d-lysergic acid diethylamide, a hallucinogen usually taken orally. For further information, see http://www.drugabuse.gov/infofacts/infofactsindex.html.

Malicious poisoning: See Nonmedical use of pharmaceuticals.

MDMA: Methylenedioxymethamphetamine, a hallucinogen with stimulant effects, usually taken orally. For further information, see http://www.drugabuse.gov/infofacts/infofactsindex.html.

Metropolitan area: An area comprising a relatively large core city or cities and the adjacent geographic areas. Conceptually, these areas are integrated economic and social units with a large population center. Unless otherwise noted, DAWN metropolitan areas correspond to Metropolitan Statistical Areas (MSAs) established by the Office of Management and Budget (OMB) based on the 2000 decennial census and updated in 2003. DAWN also prepares estimates for subsections of three of the large MSAs that correspond to MSA Divisions; in a fourth MSA, subsections were established by local users of DAWN data.

Nonmedical use of pharmaceuticals: Nonmedical use of pharmaceuticals includes taking more than the prescribed dose of a prescription pharmaceutical or more than the recommended dose of an over-the-counter pharmaceutical or supplement; taking a pharmaceutical prescribed for another individual; deliberate poisoning with a pharmaceutical by another person; and documented misuse or abuse of a prescription drug, an over-the-counter pharmaceutical, or a dietary supplement. Nonmedical use of pharmaceuticals may involve pharmaceuticals alone or pharmaceuticals in combination with illicit drugs or alcohol. Nonmedical use of pharmaceuticals includes prescription and over-the-counter pharmaceuticals in ED visits that are of the following types of cases:

(See also Drug misuse or abuse and Type of case.)

Not otherwise specified (NOS): This is the catchall category for substances that are not specifically named but are known to be reportable to DAWN. Terms are classified into an NOS category only when assignment to a more specific category is not possible based on the information in the source documentation (ED patient charts).

Not tabulated above (NTA): This designation is used when drugs or drug categories are not explicitly listed in a table. Low-incidence drugs (or drug categories) falling under a broader drug classification may be summarized into a single row under that classification and labeled as NTA.

Overmedication: See Nonmedical use of pharmaceuticals.

Oversampling: Without oversampling, one would expect a sample to resemble the population from which it was drawn. Oversampling implies the deliberate selection of a much higher proportion of certain types of sampling units than would normally be obtained in a simple, random sample. The deliberate selection of certain types of sample units is done to improve the precision of estimates of the properties of these types of sampling units. This is a form of stratified sampling. (See also Sampling, Sample frame, and Sampling unit.) In DAWN, selected metropolitan areas are oversampled so that estimates can be produced for those areas.

p-value: A measure of the probability (p) that the difference between two estimates could have occurred by chance, if the estimates being compared were really the same. The larger the p-value, the more likely the difference could have occurred by chance. For example, if the difference between two DAWN estimates has a p-value of 0.05, it means that there is no more than a 5 percent probability that the difference observed could be due to chance alone.

PCP: Phencyclidine, a hallucinogenic white crystalline powder that is readily soluble in water or alcohol or may be snorted or smoked. For further information, see http://www.drugabuse.gov/infofacts/infofactsindex.html.

Population: See Universe.

Precision: The extent to which an estimate agrees with its mean value in repeated sampling. The precision of an estimate is measured inversely by its standard error (SE) or relative standard error (RSE). In DAWN publications, estimates with RSEs greater than 50 percent are regarded as too imprecise to be published. ED table cells where such estimates would have appeared contain the asterisk symbol (*). (See also Relative standard error.)

Race/ethnicity: Race/ethnicity data in DAWN are collected retrospectively from the medical record. This approach involves a single question listing six race/ethnicity groups (plus not documented) and allows for multiple responses.1 For published reports, DAWN collapses the reported race/ethnicity information into four mutually exclusive categories, plus an unknown category, as follows:

Race/ethnicity is missing from ED patient records about 10 to 20 percent of the time, although this varies widely by hospital. In some cases, the race information is ambiguous (e.g., "European"), and detail about multiple races/ethnicities is often missing. Rates of ED visits per 100,000 are not calculated for race/ethnicity categories because of these data limitations.

Rate: A measure of the incidence of drug-related ED visits per 100,000 population. A rate can be calculated for the total population or for any subset defined by characteristics such as age and sex.

Relative standard error (RSE): A measure of an estimate's relative precision. The RSE of an estimate is equal to the estimate's standard error (SE) divided by the estimate itself. For example, an estimate of 2,000 cocaine visits with an SE of 200 visits has an RSE of 0.1 and is multiplied by 100 to change it to a percentage. This resulting RSE percent value is 10 percent. The larger the RSE, the less precise the estimate. Estimates with an RSE of 50 percent or greater are not published by DAWN. (See also Precision.)

Sample frame: A list of units from which a sample is drawn. In DAWN, the hospital is the unit used for the ED sample. All members of the sampling frame have a known probability of being selected. A sampling frame is constructed such that there is no duplication and each unit is identifiable. Ideally, the sampling frame and the universe are the same. The sampling frame for the DAWN hospital ED sample is derived from the American Hospital Association (AHA) Annual Survey Database (ASDB). (See also Universe.)

Sampling: Sampling is the process of selecting a proper subset of elements from the full population so that the subset can be used to make inference to the population as a whole. A probability sample is one in which each element has a known and positive chance (probability) of selection. A simple random sample is one in which each member has the same chance of selection. In DAWN, a sample of hospitals is selected to make inference to all hospitals; DAWN uses simple random sampling within strata.

Sampling unit: A member of a sample selected from a sampling frame. For the DAWN sample, the units are hospitals, and data are collected for drug-related ED visits at the responding hospitals selected for the sample.

Sampling weights: Numeric coefficients used to derive population estimates from a sample by adjusting for deviations from the original sample design due to unequal probability sampling, variable nonresponse, and other potential sources of bias.

Seeking detox: This category of drug-related ED visits reflects patients seeking substance abuse treatment, drug rehabilitation, or medical clearance for admission to a drug treatment or detoxification unit. They are classified separately because they often reflect administrative practices that vary across hospitals and may vary over time within the same hospital. Seeking detox visits tend to be concentrated in those facilities that operate specialized inpatient units providing substance abuse treatment or detoxification services, and the largest numbers are found in facilities that require medical clearance for entry into such treatment to be granted in their EDs.

Single-drug case: An ED visit in which only one drug was involved. The single drug may be the direct cause of the visit or a contributing factor as determined by the medical evaluation done in the ED. Because DAWN considers alcohol to be an illicit drug for minors, DAWN includes visits where alcohol is the single drug if the patient is younger than 21 years of age.

Statistically significant: A difference between two estimates is said to be statistically significant if the value of the statistic used to test the difference is larger or smaller than would be expected by chance alone. For DAWN ED estimates, a difference is considered statistically significant if the p-value is less than 0.05. (See also p-value.)

Strata (plural), stratum (singular): Subgroups of a universe within which separate ED samples are drawn. Stratification is used to increase the precision of estimates for a given sample size or, conversely, to reduce the sample size required to achieve the desired level of precision. The DAWN ED sample is stratified into metropolitan area cells plus an additional cell for the remainder of the United States. To ensure thorough coverage within metropolitan areas, the universe of hospitals in each is allocated into substrata identified by (a) two types of hospital ownership (public, private), and (b) up to four size categories (measured in terms of the number of ED visits annually). This allocation creates up to eight substrata in each metropolitan area stratum. Hospitals in the stratum that covers the rest of the United States are stratified first by census region, type of ownership, and size (also measured in terms of ED visits). A systematic sample is selected from each of the geographic strata.

Suicide attempt: This type of drug-related ED visit captures suicide attempts that are documented in the medical record and in which a drug was involved. Suicidal gestures, thoughts, or ideation, including attempts to harm oneself, are not included in this category.

Synthetic cannabinoids: Synthetic cannabinoids are substances that are designed to be chemically similar to the psychoactive ingredient in marijuana, delta-9-tetrahydrocannabinol (THC). They were initially developed over 40 years ago as therapeutic agents but more recently have been packaged as herbal smoking mixtures or "herbal incense" and marketed with claims that their effects mimic those of marijuana. Leading brands were sold under the names "Spice" and "K2," but many other brand names appeared over time; these are specified in the DAWN Drug Reference Vocabulary. A comprehensive national ban was enacted in July 2012. For further information, see http://www.drugabuse.gov/publications/drugfacts/spice-synthetic-marijuana. (See also Illicit drug use.)

Type of case: A classification used to define similar DAWN cases for analysis. Each case must be assigned a type and may not be assigned more than one type. Cases are classified into one of the following eight categories: suicide attempt, seeking detox, alcohol only (age younger than 21), adverse reaction, overmedication, malicious poisoning, accidental ingestion, and other. The case is coded into the first group that meets the inclusion criteria for that group.

Underage drinking: An ED visit where the patient is under the age of 21 and alcohol is involved. Because DAWN considers alcohol to be an illicit drug for minors, DAWN includes visits where alcohol is the only drug involved and visits where alcohol is present with other drugs.

Universe: The entire set of units for which generalizations are drawn. The universe for the DAWN ED sample is all non-Federal, short-stay, general medical and surgical hospitals in the United States that operate one or more EDs 24 hours a day, 7 days a week. Specialty hospitals, hospital units of institutions, long-term care facilities, pediatric hospitals, hospitals operating part-time EDs, and hospitals operated by the Veterans Health Administration and the Indian Health Service are excluded. The universe of EDs is identified from the American Hospital Association (AHA) Annual Survey Database (ASDB).

End Notes

1 See Office of Management and Budget, Revisions to the standards for the classification of Federal data on race and ethnicity, 62 Fed. Reg. 58,782 (October 30, 1997).



Attachment B

Drug Abuse Warning Network Methodology Report,
2011 Update


U.S. DEPARTMENT OF HEALTH AND HUMAN SERVICES
Substance Abuse and Mental Health Services Administration
Center for Behavioral Health Statistics and Quality


ACKNOWLEDGMENTS

This report was prepared by the Center for Behavioral Health Statistics and Quality (CBHSQ), Substance Abuse and Mental Health Services Administration (SAMHSA), U.S. Department of Health and Human Services (HHS), and by RTI International (a trade name of Research Triangle Institute, Research Triangle Park, NC). Work by RTI was performed under Contract No. HHSS283200700002I.

PUBLIC DOMAIN NOTICE

All material appearing in this publication is in the public domain and may be reproduced or copied without permission from SAMHSA. Citation of the source is appreciated. However, this publication may not be reproduced or distributed for a fee without the specific, written authorization of the Office of Communications, SAMHSA, HHS.

RECOMMENDED CITATION

Center for Behavioral Health Statistics and Quality (2013). Drug Abuse Warning Network Methodology Report, 2011 Update. Rockville, MD: Substance Abuse and Mental Health Services Administration.

ELECTRONIC ACCESS

This publication may be downloaded from http://store.samhsa.gov. Or please call SAMHSA at

1-877-SAMHSA-7 (1-877-726-4727)
(English and Español).

ORIGINATING OFFICE

Center for Behavioral Health Statistics and Quality
Substance Abuse and Mental Health Services Administration
1 Choke Cherry Road, Rockville, MD 20857

May 2013

CONTENTS

Introduction

1. Summary of DAWN Methodology, 2011 Update
1.1 2011 hospital participation and response rates
1.2 Determination of sample size for response rate calculation
1.3 Population estimates
1.4 Analytic groups

2. Overview of DAWN Data Program
2.1 Overview of DAWN
2.2 Hospitals eligible to participate in DAWN
2.3 ED visits eligible for inclusion in DAWN
2.4 Drugs reported for DAWN ED visits
2.5 DAWN estimates of ED visits
2.6 DAWN public use files
2.7 Uses of DAWN data

3. Information Collected by DAWN
3.1 Approach to DAWN data collection
3.2 ED visits eligible for DAWN
3.3 Case types in DAWN
3.4 Key data items
3.4.1 Patient demographics
3.4.2 Visit characteristics
3.4.3 Drugs and drug categories
3.4.4 Visit disposition

4. Development of the ED Component of DAWN
4.1 DAWN ED sample design overview
4.1.1 Sample frame of hospitals
4.1.2 Metropolitan areas represented in DAWN
4.1.3 Metropolitan-level stratification
4.1.4 Hospital size and ownership stratification
4.1.5 Sample size and sample allocation
4.2 Data collection procedures
4.2.1 Review of ED medical records
4.2.2 Selection of ED medical records
4.3 Data preparation
4.4 ED data and statistical processing
4.4.1 ED data processing
4.4.2 DAWN sample maintenance
4.4.3 Weights and adjustments
4.4.4 Sequential process of developing and applying weights and adjustments

5. DAWN Publications and Data Dissemination
5.1 Analytic groups
5.2 Drug lists
5.3 Estimates of visits versus drugs
5.4 Standardized rates
5.5 Population estimates used to calculate rates
5.6 Measures of precision and error
5.7 Suppression
5.8 Cross-year comparisons
5.9 DAWN public use files

6. Quality Assurance/Quality Control
6.1 Minimization of nonsampling error
6.1.1 Maintaining data quality during data collection and data preparation
6.1.2 End-of-year data quality review
6.2 Minimization of sampling error
6.3 Quality control on released reports and tables

7. Data Limitations
7.1 Limitations of survey data
7.2 Limitations of using extant medical records
7.3 Limitations on toxicology test finding

8. History of DAWN, 1970–2012

List of Figures

Figure 1. Type of case decision tree
Figure 2. DAWN ED case form

List of Tables

Table 1. Drug-related ED visits and drugs, by type of case, 2011
Table 2. DAWN sample characteristics, 2011
Table 3. U.S. population, by age and sex, 2011
Table 4. DAWN analytic groups
Table 5. Data items in the data quality review spreadsheet

INTRODUCTION

This publication describes the methodologies used by the Drug Abuse Warning Network (DAWN), a program of the Center for Behavioral Health Statistics and Quality (CBHSQ), Substance Abuse and Mental Health Services Administration (SAMHSA), to collect, prepare, and analyze information on drug-related emergency department (ED) visits in the United States. An understanding of the methodology behind the collection and processing of DAWN data allows data users to better evaluate the validity, representativeness, and meaning of the findings. The methods described here were initiated in 2004 and are current as of 2011. Comparisons across data collection years can only be made for 2004–2011. Due to changes introduced to core survey features—such as the design of the sample, protocol for selecting charts to review, and the eligibility criteria for being a DAWN case in 2004—DAWN data for 2004 and forward are not comparable to data for earlier years (2003 and earlier).

This report is organized into eight parts:

  1. Summary of DAWN Methodology, 2011 Update—Methodological highlights of the 2011 data collection year.
  2. Overview of the DAWN data program—Brief summary of DAWN and its purpose.
  3. Information collected by DAWN—What constitutes a drug-related ED visit and the data items collected for each visit.
  4. Development of the ED component of DAWN—How DAWN data on drug-related ED visits are collected and processed to make representative national and metropolitan area estimates using survey data.
  5. DAWN publications and data dissemination—How DAWN data are organized, summarized, and presented to address different statistical and analytic goals.
  6. Quality assurance/quality control—Methods and procedures used to ensure that DAWN data are as accurate, precise, and reliable as possible.
  7. Data limitations—DAWN collects data on ED visits from a sample of hospitals and relies solely on existing medical records maintained by these hospitals; as a result, there are some limitations to consider when interpreting results.
  8. History of DAWN, 1970–2012—How DAWN came into existence and has been maintained for over 40 years.

For convenience, the 2011 DAWN ED Annual Report includes as attachments all methodological documents related to the 2011 data collection year. These attachments include the following:

These items individually as well as additional information about DAWN are provided on the DAWN Web site.1 Available at the site are

1. SUMMARY OF DAWN METHODOLOGY,
2011 UPDATE

This section documents the participation of sampled hospitals in 2011 and other survey methodology information relevant for the Drug Abuse Warning Network (DAWN) data collection year 2011. Additional detail on the basic DAWN data collection and survey methodology is provided in subsequent sections.

1.1 2011 hospital participation and response rates

DAWN relies on a longitudinal probability sample of hospitals located throughout the United States, including Alaska and Hawaii. To be eligible for selection into the DAWN sample, a hospital must be a non-Federal, short-stay, general surgical and medical hospital located in the United States, with at least one 24-hour emergency department (ED).

For data collection year 2011, data were collected from a representative sample of hospitals in the Nation and select metropolitan areas. Over 5 million ED visit charts out of a universe of 12.2 million charts at reporting hospitals were reviewed.2 Data submitted by 233 participating hospitals on 229,211 drug-related ED visits were used in estimation (Table 1).3

Estimates for the entire universe of DAWN-eligible hospitals in the United States are produced by applying poststratified weights to the data received from the participating sampled hospitals. Thus, for 2011, a total of 229,211 submitted cases was extrapolated to an estimate of 5,067,374 drug-related ED visits. Considering the margin of error, this estimate may range from 4,616,753 to 5,517,995 drug-related ED visits out of the approximately 126 million total ED visits estimated for the universe of DAWN-eligible hospitals. Of these approximately 5.1 million drug-related visits, 2.5 million were considered to involve drug misuse or abuse, with the balance primarily involving adverse reactions and accidental ingestions.

Table 1. Drug-related ED visits and drugs, by type of case, 2011
Type of visit Unweighted
sample data
Weighted
estimates
RSE (%) 95% CI:
Lower bound
95% CI:
Upper bound
(1) Estimates of ED visits are based on a representative sample of non-Federal, short-stay hospitals with 24‑hour EDs.
(2) These are estimates of drugs involved in ED visits. Because a single ED visit may involve multiple drugs, the number of drugs is greater than the number of visits.
NOTE: CI = confidence interval. RSE = relative standard error. A dash (—) indicates a blank cell.
SOURCE: Center for Behavioral Health Statistics and Quality, SAMHSA, Drug Abuse Warning Network, 2011.
Drug-related ED visits (1)                                                         
Drug-related suicide attempt          9,033        228,366   6.8    197,745    258,986
Seeking detox        14,841        250,596 29.3    106,830    394,363
Alcohol only (age < 21)          7,486        117,653 10.6      93,260    142,047
Adverse reaction        88,096     2,301,059   6.2 2,021,724 2,580,394
Overmedication        18,146        432,400   4.6    393,168    471,632
Malicious poisoning             793          15,471 10.2      12,388      18,554
Accidental ingestion          3,253        113,624   9.8      91,749    135,499
Other        87,628     1,609,364 10.3 1,284,525 1,934,203
Total drug-related ED visits      229,211     5,067,374   4.5 4,616,753 5,517,995
Total drug misuse or abuse visits      131,698     2,462,948   7.3 2,112,868 2,813,028
Total ED visits (all reasons) 11,791,257 126,427,426   0.0            —            —
Drugs (2)                                                         
Drug-related suicide attempt        19,461        517,879   8.4    432,155    603,603
Seeking detox        30,455        532,155 30.2    216,815    847,495
Alcohol only (age < 21)          7,486        117,653 10.6      93,260    142,047
Adverse reaction      118,590     3,074,260   7.3 2,633,505 3,515,015
Overmedication        32,939        815,597   5.7    724,093    907,101
Malicious poisoning          1,446          28,655 10.6      22,687      34,624
Accidental ingestion          4,302        148,234   9.5    120,724    175,744
Other      148,480     2,812,982 10.9 2,213,457 3,412,508
Drugs in all drug-related ED visits      363,094     8,046,258   6.6 7,009,793 9,082,723
Drugs in all misuse or abuse ED visits      230,763     4,510,768   8.5 3,758,582 5,262,954

Table 2 lists hospital, design, and visit response rates for the Nation and the 12 metropolitan statistical areas (MSAs) that had sufficient participation in 2011 to warrant separate estimates. The national hospital response rate was 41.5 percent; the design weight response rate was 29.2 percent; and the visits weighted response rate was 35.2 percent. At the metropolitan area level, the hospital response rate ranged from 23.5 percent to 82.6 percent; the design weight response rate ranged from 23.5 percent to 82.6 percent; and the visit weighted response rate ranged from 21.8 percent to 89.7 percent.

Table 2. DAWN sample characteristics, 2011
Geographic area Total
eligible
hospitals (1)
Eligible
hospitals in
sample (1)
Responding
hospitals in
sample
Response
rate for
sampled
hospitals (%)
Design
weight
response rate
(%)
Visits
weighted
response rate
(%)
(1) General, non-Federal, short-stay hospitals in the United States with 24-hour EDs, based on the American Hospital Association Annual Survey, are eligible for DAWN.
(2) The total number of eligible hospitals includes the sampled and participating hospitals from metropolitan areas shown in this table, plus hospitals in the remainder of the United States. Components shown here do not sum to the total.
(3) Unless otherwise noted, DAWN defines metropolitan areas using the MSA and Division definitions issued by the Office of Management and Budget in June 2003 (available at http://www.whitehouse.gov/omb/bulletins/b03-04.html).
(4) Miami-Miami Beach-Kendall, FL, Division.
(5) Fort Lauderdale-Pompano Beach-Deerfield Beach, FL, and West Palm Beach-Boca Raton-Boynton Beach, FL, Divisions.
(6) Bronx, Kings, New York, Queens, and Richmond Counties, NY.
(7) San Francisco-San Mateo-Redwood City, CA, Division.
NOTE: MSA = Metropolitan Statistical Area.
SOURCE: Center for Behavioral Health Statistics and Quality, SAMHSA, Drug Abuse Warning Network, 2011.
Total United States (2,3) 4,648 562 233 41.5 29.2 35.2
Boston-Cambridge-Quincy, MA-NH, MSA      40   29   19 65.5 65.5 63.8
Chicago-Naperville-Joliet, IL-IN-WI, MSA      89   72   31 43.1 44.6 40.3
Denver-Aurora, CO, MSA      17   16   11 68.8 68.8 77.1
Detroit-Warren-Livonia, MI, MSA      36   24   17 70.8 69.5 85   
Houston-Baytown-Sugar Land, TX, MSA      59   46   14 30.4 30.8 21.8
Dade County Division of Miami-Fort Lauderdale-Miami Beach, FL, MSA (4)      21   16     9 56.3 51.7 56.8
Fort Lauderdale and West Palm Beach Divisions of Miami-Fort Lauderdale-Miami Beach, FL, MSA (5)      31   22     8 36.4 32.1 50.1
Minneapolis-St. Paul-Bloomington, MN-WI, MSA      29   27   12 44.4 44.4 54.4
New York—Five Boroughs (part of Newark-Edison, NY-NJ-PA, MSA) (6)      44   34   22 64.7 61.1 72.6
Phoenix-Mesa-Scottsdale, AZ, MSA      31   29   13 44.8 44.8 53.1
San Francisco Division of San Francisco-Oakland-Fremont, CA, MSA (7)      20   17     4 23.5 23.5 25.6
Seattle-Tacoma-Bellevue, WA, MSA      24   23   19 82.6 82.6 89.7

1.2 Determination of sample size for response rate calculation

In 2011, the initial DAWN sample included 1,292 hospitals divided among 48 metropolitan areas, 9 submetropolitan areas, and 1 area representing hospitals located outside those metropolitan areas. Response rates and nonresponse bias were assessed to determine which of these areas had sufficient participation to warrant separate estimates. In 2011, a total of 12 areas (9 metropolitan areas and 3 submetropolitan areas) was determined to be able to support separate estimates. Oversampled hospitals in the areas that could not support separate estimates were treated as if they were not sampled. For 2011, this has the effect of reducing the sample from 1,292 hospitals to 562 hospitals, the number used for purposes of computing the overall response rates.

1.3 Population estimates

Population estimates used to generate rates (visits per 100,000 population) for 2011 are provided in Table 3.

Table 3. U.S. population, by age and sex, 2011
Age Total United States Males Females
SOURCE: U.S. Census Bureau, United States Resident Population Estimates by Age, Sex, Race, and Hispanic Origin (Vintage 2011).
Total 311,591,917 153,290,819 158,301,098
0–5 years   24,250,207   12,389,387   11,860,820
6–11 years   24,575,696   12,552,757   12,022,939
12–17 years   25,108,369   12,862,935   12,245,434
18–20 years   13,506,990     6,933,789     6,573,201
21–24 years   17,557,719     8,963,495     8,594,224
25–29 years   21,279,794   10,761,515   10,518,279
30–34 years   20,510,704   10,282,648   10,228,056
35–44 years   40,627,954   20,223,470   20,404,484
45–54 years   44,718,203   22,019,247   22,698,956
55–65 years   38,062,140   18,358,205   19,703,935
65 years and older   41,394,141   17,943,371   23,450,770

1.4 Analytic groups

DAWN produces estimates of ED visits for different types of visits, referred to as DAWN analytic groups. The analytic groups are defined by the reason for the visit and the types of drugs involved (see Section 5.1). Unlike the type of case categories, DAWN analytic groups are not mutually exclusive. For example, a visit that involves cocaine and oxycodone will be counted in both the illicits analytic group and the nonmedical use of pharmaceuticals analytic group.

The total number of ED visits for the seven analytic groups related to drug misuse or abuse are as follows:

Estimates for ED visits related to adverse reactions to and accidental ingestions of pharmaceuticals, medications, and other health-related products available over the counter are also produced. These groups are not related to drug abuse or misuse and are as follows:

2. OVERVIEW OF DAWN DATA PROGRAM

2.1 Overview of DAWN

DAWN is a public health surveillance system that reports on drug-related visits to hospital EDs.4 DAWN is used to monitor trends in drug misuse and abuse, identify the emergence of new substances and drug combinations, assess health hazards associated with drug use and abuse, and estimate the impact of drug use, misuse, and abuse on the Nation's health care system.

2.2 Hospitals eligible to participate in DAWN

DAWN's target sample frame consists of all non-Federal, short-stay, general medical and surgical hospitals in the United States that have one or more EDs open 24 hours a day. DAWN employs a multistage sampling design for the selection of EDs for analysis. Stratified simple random sampling with oversampling in selected metropolitan areas is used to select the hospitals.

2.3 ED visits eligible for inclusion in DAWN

A DAWN case is any ED visit involving recent drug use. DAWN cases are identified through the review of ED medical records in participating hospitals. DAWN captures both ED visits that are directly caused by drugs and those in which drugs are a contributing factor but not the direct cause of the ED visit. These criteria encompass all types of drug-related events, including accidental ingestion and adverse reaction, as well as drug misuse or abuse. Within each hospital, 50 percent to 100 percent of the days of the month are systematically selected, and a census of ED visits is selected for review for these days.

2.4 Drugs reported for DAWN ED visits

DAWN collects data on all types of drugs—illegal drugs, prescription and over-the-counter medications, dietary supplements, and both pharmaceutical and nonpharmaceutical inhalants. DAWN notes whether alcohol is involved in addition to drug(s) for patients of all ages. Because alcohol is considered an illicit drug for minors, alcohol abuse without the involvement of other drugs is considered a drug-related ED visit for patients under the age of 21. DAWN does not report current medications (i.e., medications and pharmaceuticals taken regularly by the patient as prescribed or indicated) that are deemed by the ED medical staff to be unrelated to the ED visit.

DAWN classifies drugs using a modified version of the Multum Lexicon, © 2012, a drug vocabulary and classification tool originated by Multum Information Services, Inc. DAWN has adapted the Lexicon to allow for the inclusion of illegal drugs, inhalants, and alternative medicines that are reported to DAWN.

2.5 DAWN estimates of ED visits

Annually, DAWN produces estimates of drug-related visits to hospital EDs for the Nation as a whole and for selected metropolitan areas. DAWN Trend Tables contain weighted estimates of drug-related ED visits that are the result of drug misuse or abuse, adverse reactions to drugs, and accidental ingestion of drugs. Among visits resulting from drug misuse or abuse, separate estimates are made of visits involving illicit drugs, nonmedical use of pharmaceuticals, and alcohol. Estimates are also made of ED visits resulting from drug-related suicide attempts, ED visits made by patients seeking detoxification services, and visits involving alcohol (with or without other drugs) for patients under the age of 21. For each of these types of visits, estimates are available by patient sex, age group, and race/ethnicity. Estimates are also provided for each visit's disposition (e.g., treated and released, admitted to the hospital intensive or critical care unit [ICU], died). Estimates are made of the different types of drugs involved in each of these categories of visits. These sets of estimates are prepared for the Nation as a whole and for selected metropolitan areas where hospital participation was high enough to produce reliable results.

DAWN Trend Tables containing ED estimates are available at the DAWN Web site.5 The document Guide to the DAWN Trend Tables provides guidance on accessing these tables, understanding their content, and locating data items of interest.6

2.6 DAWN public use files

The DAWN public use file (PUF) containing ED visit-level data is available through the Substance Abuse and Mental Health Data Archive (SAMHDA).7 The SAMHDA site offers a query capacity to build tables online using the DAWN PUF data as well as the means to download data files. The presentation Analyzing the Drug Abuse Warning Network (DAWN) Data available at the DAWN Web site provides guidance on accessing, interpreting, and analyzing DAWN PUF data. Additional detailed documentation for the DAWN PUF is also available at the SAMHDA site. The weights needed to produce estimates representative of the Nation and select metropolitan areas are provided in the DAWN PUF. A lengthier description of SAMHDA's services is provided in Section 5.9 of this document.

2.7 Uses of DAWN data

DAWN is a major component of the Nation's capacity to monitor trends in the morbidity and mortality associated with drug misuse and abuse. DAWN is the only national data system providing estimates of the number of ED admissions associated with drug misuse and abuse and the particular drugs involved both for the United States as a whole and also for selected metropolitan areas. Additionally, DAWN is the only national data collection system on drug abuse with the capacity to monitor specific and relatively infrequently used substances of abuse (e.g., club drugs, phencyclidine [PCP], or medications used to treat attention deficit hyperactivity disorder [ADHD]) as they emerge and diffuse across population groups and geographic areas.

Within the Substance Abuse and Mental Health Services Administration (SAMHSA), DAWN data help SAMHSA to target program resources to areas of greatest need and to assess program impact. For example, as part of its intervention programming, SAMHSA uses DAWN data to monitor adverse events associated with buprenorphine treatment for opiate addiction. Additionally, DAWN data are used by the Center for Behavioral Health Statistics and Quality (CBHSQ) to prepare reports on topics of interest to the public health community, to provide regular updates to SAMHSA and other federal agencies on trends in drug involvement, and to respond to ad hoc inquiries from public health researchers. DAWN estimates are used to monitor trends in major substances of abuse (e.g., heroin, cocaine, marijuana); to assess alcohol use by minors that results in ED visits; to identify emerging new drugs of abuse (e.g., synthetic cannabinoids, "bath salts"); and to identify the misuse and abuse potential of prescription and over-the-counter drugs. The DAWN Web site provides a complete listing of all publicly available reports developed by SAMHSA using DAWN data.

Outside of SAMHSA, DAWN is used by national, state, and local health professionals, policymakers, law enforcement officers, and pharmacologists to understand the consequences of drug use and abuse and to identify emerging trends and changing patterns of drug use. The White House Office of National Drug Control Policy uses DAWN data to monitor national trends; the Drug Enforcement Administration uses it for surveillance, diversion control, and intelligence; and, at the direction of the Food and Drug Administration, the pharmaceutical industry uses it to conduct post-marketing surveillance of prescription and over-the-counter pharmaceuticals, monitor adverse events associated with medications, and assess the abuse potential that drives labeling and scheduling decisions. State and local professionals, including law enforcement and the Community Epidemiology Work Group, use DAWN to assess changes in local trends and patterns of drug use.

3. INFORMATION COLLECTED BY DAWN

3.1 Approach to DAWN data collection

DAWN data are collected through a retrospective review of ED medical records for patients treated in the ED. Patients or families are never interviewed. The review of source records is performed by a trained DAWN Reporter in each member facility. Depending on the needs of the facility, the DAWN Reporter may be an employee of the hospital or an employee of the DAWN operations contractor. For each facility that participates in DAWN, the designated DAWN Reporter reviews all medical records to find ED visits related to drug use. The DAWN Reporter submits an electronic case report to the DAWN system for each ED visit that meets the specific case selection criteria. DAWN Reporters also track, on a copy of the ED registration log, their progress in reviewing the universe of ED visits. Because of the volume in some EDs, a sample of medical records is obtained rather than reviewing a census. This subsampling introduces another component of variance that is accounted for in the weighting and estimation process.

3.2 ED visits eligible for DAWN

A DAWN case is any ED visit where the patient was treated in the ED for a condition that was induced by or related to recent drug use. The patient chart is reviewed by the DAWN Reporter to determine if there is evidence that a drug(s) is involved. The patient ED chart has three key areas, and this evidence may come from any one of these areas: patient's chief complaint; physician's, nurse's, and/or other appropriate clinician's assessment; and/or diagnosis detail. The drug use must be implicated in the ED visit, but it does not need to be the direct cause. The reason a patient used a drug is not a factor in determining whether the ED visit is a DAWN case. Only drugs that are determined to be involved are recorded in the DAWN system. Unrelated drugs that are simply "on board" are not recorded.

As a result of these criteria and approaches, DAWN includes ED visits associated with substance abuse and misuse, both intentional and accidental, as well as ED visits related to the use of drugs for legitimate therapeutic purposes and under a doctor's direction. The DAWN visit eligibility criteria are intended to be broad and inclusive and to have few exceptions. They take into account the fact that documentation in medical records varies in clarity and completeness across hospitals and among clinicians within hospitals. The criteria are designed to minimize the potential for DAWN Reporter judgments that could cause data to vary systematically and unexpectedly across different data collectors and hospitals. In addition, the criteria allow for the capture of a diverse set of drug-related visits that can be aggregated or disaggregated to serve a variety of analytical purposes and the interests of multiple audiences.

There are a few clearly delineated exceptions to the DAWN eligibility criteria. An ED visit is not a DAWN visit if

3.3 Case types in DAWN

By design, DAWN's broad case criteria yield a diverse set of visits. To bring order to this heterogeneous mix of ED visits, DAWN Field Reporters assign each visit to one of eight case types.8 The eight case types are as follows:

Each ED visit is assigned to a single case type. Because many ED visits meet the criteria for more than one case type, the case types are assigned based on an algorithm depicted in the DAWN Decision Tree (Figure 1). Each ED visit is assigned to the first applicable case type. To assist DAWN Reporters with case assignment, a series of questions and decision rules is included with the DAWN Decision Tree; detailed instructions are included in the 2007–2011 ED Reference Guide.9

The final category in the decision tree, Other, is reserved for DAWN visits that do not meet any of the rules for classification into one of the first seven types. Most cases of drug abuse are classified as Other. This approach, which never directly identifies drug abuse, comes from the recognition that medical records frequently lack explicit documentation of substance abuse. This lack of documentation may occur for several reasons. First, the distinctions among use, misuse, and abuse are often subjective. Second, if there is a low index of suspicion for drug abuse in some types of patients (e.g., older adults), ED physicians may be unlikely to label those types of patients as drug abusers. Third, ED staff may be concerned that the patient's insurance company will disallow coverage if the visit is related to substance abuse.

The case type of a visit, in combination with the types of drugs involved, is used to construct groupings of visits that have similar characteristics—for example, visits for drug abuse involving illicit drugs. Section 5.1 provides additional details on how visits are grouped for the purpose of analyses.

Figure 1. Type of case decision tree

Figure 1     D

3.4 Key data items

Figure 2 depicts the data items collected by DAWN. Additional detail on key items is provided in the following sections.

Figure 2. DAWN ED case form

Figure 2     D

3.4.1 Patient demographics

DAWN collects information on basic patient demographics: sex, age, race/ethnicity, and patient home ZIP code. The ZIP code variable has space to indicate if the patient was homeless, institutionalized, or from outside the United States and, therefore, has no home ZIP code.

For reporting purposes, age is typically collapsed into the following groups:

The age categories used for reporting ED visits reflect critical junctures in drug use. For example, patients aged 5 and under are reported separately to facilitate study of visits involving accidental ingestion. Patients aged 12 to 17 are considered to be in their formative years, and understanding the nature of their drug use is important for prevention efforts. Patients under the age of 21 are reported separately to facilitate study of topics such as underage drinking. Patients aged 18 to 20 are reported separately from those aged 21 to 24 to isolate drug-taking behaviors before and after the critical age of 21. Older patients are grouped in wider categories where age differences are not as critical to intervention and treatment. As a consequence, the age categories are not evenly sized—for example, the age group 30 to 34 covers 5 years, whereas the age group 35 to 44 covers 10 years. The size of an age group is an important consideration when comparing estimates of ED visits for different age categories.

ED records vary in the level and type of detail provided. Although sex, age, and ZIP code are usually present in patients' ED records, race/ethnicity is often missing or insufficient (e.g., "European"). Although it is possible to record multiple race/ethnicities, for reporting purposes race/ethnicity is collapsed into a single variable with five levels:

3.4.2 Visit characteristics

DAWN collects detailed information about each visit. The data items include

DAWN Reporters also provide a brief description of the visit, drawn directly from the ED record, which includes the reason for the visit and any other information necessary to document that the visit is a DAWN case.

3.4.3 Drugs and drug categories

For the purpose of DAWN, a drug is any substance that is (a) used as a medication or in the preparation of medication; (b) an illicit substance that causes addiction, habituation, or a marked change in consciousness; or (c) both. Substances reportable to DAWN include illicit drugs (e.g., club drugs, cocaine, heroin, marijuana, stimulants, and alcohol when used by a minor10), nonpharmaceutical inhalants,11 prescription drugs (e.g., drugs for ADHD, antibiotics, antidepressants, antipsychotics, anticoagulants, beta blockers, birth control pills, hormone replacement, insulin, muscle relaxants, pain relievers, sleeping aids), drugs used in treatment of medical conditions (e.g., respiratory therapy, chemotherapy, radiation therapy), vaccines, dietary supplements, vitamins, and other over-the-counter pharmaceutical products.

Using the DAWN Drug Reference Vocabulary (DAWN DRV), DAWN is able to identify more than 3,300 individual drugs (which map to more than 19,000 individual brands and street names). The DAWN DRV is a comprehensive drug vocabulary and classification system based on the Multum Lexicon, © 2012, that has been modified to meet DAWN's unique requirements. The DRV includes codes for brand (trade) names, generic names, chemical names, metabolites, nonspecific drug terms, and street terms for legal and illegal substances, including prescription and over-the-counter pharmaceuticals and selected nonpharmaceuticals that are abused by inhalation.

DAWN Reporters collect the most specific information about each drug that is available in the ED record. Up to 22 drugs implicated in a visit are assigned a code using the DRV. Because multiple substances can be reported for each DAWN case, the total number of drugs exceeds the total number of DAWN cases reported.

The DRV provides the flexibility needed to accommodate the varying level of drug detail provided in ED records. A drug might be recorded in the ED records by its brand name (e.g., OxyContin®), a generic name (e.g., oxycodone), or by the class to which it belongs (e.g., an unspecified narcotic pain reliever). Each of these has a code in the DRV. Narcotic pain relievers are mapped to the larger grouping "Opioid/opiate Pain Relievers," which is part of the broader category "Pain Relievers," which is one of the categories among "Central Nervous System Agents." Illicit drugs and other DAWN-reportable substances are maintained in a similar tiered structure in the DRV.

The Multum Lexicon is updated every 2 months to incorporate new products and, occasionally, to introduce new drug categories. Through the end of data collection year 2011, the DAWN DRV was updated to incorporate those changes as well as include any drugs reported by EDs that were not in the Multum Lexicon (e.g., imported drugs, new combinations of illicit drugs). At the end of each data year, all the drug data received from EDs—the current year's data and data from all previous years—were coded using the most recent DRV. This process ensures that estimates of visits by drug across years are comparable.

Additional information on the Multum Lexicon, © 2012, the DAWN DRV, and the Multum Licensing Agreement governing use of the Lexicon can be found on the DAWN Web site.12 Readers interested in exploring the DRV and the manner in which it classifies drugs may obtain the full set of DAWN DRV tables in the relational database named "DAWN_DRV.mdb."13 Queries are used to join tables and display relationships between different drugs and drug groupings. The DRV is also available as a spreadsheet named "DAWN__Final_Table.xls."

3.4.4 Visit disposition

The visit disposition records where the patient went after leaving the ED. There are three major categories: treated and released, admitted to this hospital, and other dispositions. Additional detail is provided with subcategories.

Treated and released includes three categories:

Admitted to this hospital includes five categories of inpatient units:

Other disposition includes five categories:

Visit dispositions may be reported using the three major categories or 13 subcategories, as noted above. A third way of reporting disposition that often appears in DAWN reports and tables groups ED visits based on whether there is any indication in the ED record that the patient received some type of follow-up treatment. "Evidence of follow-up" includes patients who were referred to detox/treatment, admitted to the hospital (any unit), or transferred. "No evidence of follow-up" includes patients with any other disposition.

4. DEVELOPMENT OF THE ED COMPONENT OF DAWN

4.1 DAWN ED sample design overview

The statistical and methodological design of the current DAWN system was introduced in data collection year 2004. A new stratified simple random sample of hospitals was drawn at that time from among the universe of eligible hospitals in the Nation; oversampling was conducted in selected metropolitan areas.15 For each participating sampled hospital and for each month of the year, days of the month are systematically selected and all ED visits for these days are reviewed for eligibility as DAWN cases. Data collection following the new sampling plan was fully implemented for the first time in the 2004 data collection year, and the original sample of hospitals has been followed longitudinally since then. That is, each year since 2004, new hospitals are given the opportunity to be sampled into the longitudinal panel of hospitals.

4.1.1 Sample frame of hospitals

The DAWN sampling frame was built from among all hospitals meeting the DAWN criteria for eligible hospitals (i.e., non-Federal, short-stay, general medical and surgical hospitals in the United States that have one or more EDs open 24 hours a day, 7 days a week) that appeared on the 2001 American Hospital Association (AHA) Annual Survey Database (ASDB).16 A probability sample proportionate to the number of ED visits in each facility was drawn from among eligible hospitals.

4.1.2 Metropolitan areas represented in DAWN

Samples were drawn from the initial frame to provide the capability to make estimates for the Nation as well as selected metropolitan areas. The metropolitan areas are referred to as oversampled areas (OS areas) or DAWN metropolitan areas. Two goals guided the selection of the DAWN metropolitan areas. The first was to preserve the ability to represent the 21 areas that had been part of DAWN since its inception. The second was to improve population and geographic coverage beyond these 21 legacy areas. Accordingly, the design ensured representation of the original 21 legacy areas plus the 5 most populous MSAs in each of the 9 census divisions. Oversamples were selected in a total of 48 MSAs; in 4 of those 48 MSAs, additional oversamples were drawn to allow reporting for subareas within those MSAs. Resources available to DAWN have allowed for data collection in only a portion of the OS areas.

4.1.3  Metropolitan-level stratification

The DAWN sample design was conceived to provide the statistical infrastructure to produce reliable and representative estimates for the Nation and a portion of DAWN metropolitan areas (OS areas), depending on available resources and interest. To accomplish this objective, a subset of the hospitals within each OS area was identified a priori as having a dual purpose in estimation. Referred to as dual-purpose hospitals, these designated hospitals can contribute either to an estimate for the OS area in which they are located or to the estimate for the remainder area outside of OS areas. Dual-purpose hospitals carry two probabilities of selection (POS) and two stratum identifiers. One POS/stratum is associated with membership in an OS area oversample, and the other is associated with membership in the remainder area sample.17

Each data year, the response rates and nonresponse patterns for each OS area are reviewed to determine data quality. Those OS areas with acceptable data quality are allowed to stand on their own as the basis for separate estimates; they are referred to as stand-alone OS areas. If it is determined on the basis of response rates and bias analyses that an OS area cannot stand alone, the design provides that the OS area is eliminated as a separate area but becomes part of the remainder area.

DAWN national-level estimates are the sum of the estimates for stand-alone OS areas plus the remainder area. The formula for the national estimate is

This equation is used to calculate a national estimate as the sum of the N stand-alone oversample area estimates (a subscript i) plus the estimate for the remainder area (b), which includes the 53-N oversample areas that do not stand alone.

where ai is the estimate for stand-alone OS area i, N is the number of stand-alone OS areas, and b is the remainder area estimate inclusive of dual-purpose hospitals in OS areas that do not stand alone.

4.1.4 Hospital size and ownership stratification

Sampled hospitals in each of the OS areas were stratified by hospital size (up to four categories, on the basis of the number of ED visits18) and ownership type (public and private). The stratification plan included an additional geographic construct to represent the remainder of the United States outside the OS areas. Hospitals in the remainder area were divided into 24 strata on the basis of four regions (Northeast, South, Midwest, West), three size categories, and ownership type.

4.1.5 Sample size and sample allocation

Each hospital in the DAWN sample was selected through a random process, which theoretically could have been repeated many times, resulting in many hypothetical samples. Sampling variance, or the margin of error, refers to the extent to which these samples were likely to have varied. Two measures of this variability are the standard error (SE) and the relative standard error (RSE), which is defined as the SE of the estimate divided by the estimate itself. The precision of an estimate is inversely related to the sampling variance, as measured by the RSE. The greater the RSE value, the lower the precision. DAWN is designed to have estimates for major drug categories (i.e., all drug-related ED visits plus ED visits for cocaine, heroin, and marijuana), wherein the RSEs are less than or equal to 10 percent for metropolitan area estimates and less than or equal to 15 percent for national estimates. Sample sizes for each metropolitan area and the Nation were set using these targeted precision levels in combination with the theory of optimal allocation for stratified samples.

4.2 Data collection procedures

This section documents the methodologies used to collect DAWN data. The DAWN operations contractor (DOC) is responsible for collecting DAWN data. Additional detail on data collection methodology is available in the 2007–2011 ED Reference Guide.19

4.2.1 Review of ED medical records

DAWN ED data are collected directly from the medical records of patients treated in the ED. The review is done after the ED visit is completed. Patients, their families, and clinical staff are never interviewed. The data are collected by trained DAWN Reporters who review ED medical records to identify ED visits related to recent drug use. For each DAWN case, an electronic case report is completed (Figure 2, in Section 3, depicts the data elements collected). Case reports are submitted electronically using the Electronic Hospital Emergency Reporting System (eHERS), a customized system developed specifically for DAWN. DAWN Reporters also submit an activity report detailing their progress in reviewing the ED charts, and they report the monthly census of all ED visits made to the hospital. Data collection is performed on an ongoing basis as soon after the ED visit as possible.

The majority of DAWN ED data are collected on site at hospitals by a DAWN Reporter who reviews paper or electronic records. A growing number of hospitals have centralized electronic medical records systems that can be accessed from the outside. In these cases, DAWN Reporters access the systems via remote access from the DOC's headquarters. A secured transmission line is maintained for this purpose by the DOC.

4.2.2 Selection of ED medical records

The original DAWN redesign protocol called for direct review of all available ED records. After careful review and testing, however, it was established that a sample of ED visits could be used to produce sufficiently precise estimates in comparison to a census of visits provided that the cost savings be redirected toward recruiting additional hospitals. In 2008, a protocol was developed for drawing a systematic sample of each ED's medical records based on the date of the ED visit. In those EDs with sampling, the DAWN Reporter is sent a list each month of designated dates for chart review, and the charts for all the ED visits occurring on the designated dates are reviewed for drug-related visits. By 2010, sampling of ED records had been introduced in all larger hospitals and many smaller ones.

A vast majority of sampled records are reviewed, but there are some instances when they are not. Unintentional gaps in chart review may occur due to such factors as a DAWN Reporter's unexpected absence or circumstances at the hospital that preclude review of some ED records (e.g., limitations on the hours or days that a DAWN Reporter may access ED records, removal of records from facility). A similar method of within-hospital visit weighting is used to compensate for both intentional sampling of ED records as well as unintentional gaps in record review (see Section 4.4.3).

4.3 Data preparation

The DOC performs numerous reviews that begin at the point of entry and continue through the final delivery of the data to SAMHSA. Automated systems check DAWN case data to confirm eligibility of cases submitted and for case type discrepancies. In addition, edit programs are run to identify range and consistency errors. "Unknown" drugs entered by the DAWN Reporter are reviewed by CBHSQ; when possible, they are upcoded to extant codes or new drug codes are added to the DRV, when appropriate. At the end of every data collection year, an extensive data review is conducted. Statistical process control (SPC) is used to evaluate the monthly counts of ED visits, charts reviewed, and cases reported for each ED. If any monthly count of visits, charts, or cases is identified as inconsistent by SPC, that count is investigated via communication with contacts from the ED. The results of the investigation are documented and sent along with the final delivery. As a final step, the SPC results and monthly counts for each ED are reviewed by the DOC, the Data Analysis Contractor (DAC), and representatives from CBHSQ.

4.4 ED data and statistical processing

The DOC prepares the database as described in Section 4.3, at which point the annual data files and the current DRV are transferred to the DAC. The DAC performs a number of data quality and data processing steps to prepare the file for weighting and for developing estimates (see Section 4.4.1). Sample maintenance is then performed (see Section 4.4.2). Weights and adjustments are then developed (see Section 4.4.3). Section 4.4.4 describes the sequential processing steps for developing and applying weights and adjustments.

4.4.1 ED data processing

Because up to 22 drugs may be reported for each visit, the DAC begins its processing by ensuring that no duplicate drugs are recorded for a visit. The DRV, the database that defines how drugs are classified and mapped to drugs, is applied to the microdata received from the DOC to derive drug IDs and the standard drug list (SDL) classification associated with each drug.20 The resulting drug IDs for a visit are compared with one another to ensure that a drug appears only once for a visit.21 After the initial deduplication, codes for mouthwash and alcohol are deduplicated. Lastly, a check is run to ensure there are no cases that involve only alcohol for respondents aged 21 or older. The data are classified originally on a brand level and then are processed to a drug ID level; a final step is to flatten the data file to a visit level. Discrepancies or irregularities are resolved through discussion among the DOC, the DAC, and the DAWN team at CBHSQ.

4.4.2 DAWN sample maintenance

As noted above, the initial DAWN sample was selected from a sampling frame created from the 2001 AHA ASDB. Because DAWN is a longitudinal survey, maintenance is conducted every year to ensure that the sample remains representative of the target population of eligible hospitals. Over time, new hospitals will be opened, some will close, some will merge with other hospitals, and some will "demerge" to form two or more smaller hospitals. Some hospitals no longer maintain 24-hour EDs and become ineligible; others open them and become eligible. Each year the sampling frame is updated to reflect new, closed, merged, and demerged hospitals on the basis of information in the most current AHA ASDB. Since 2004, a master file has been maintained of the changes to the frame and originally sampled hospitals, plus information on all new frame and sampled hospitals. All variables in the AHA master file are assigned consistent names from year to year, even if there are variable name changes in later AHA ASDBs. Conversely, documentation accompanying the AHA ASDB each year is carefully reviewed to ensure that variables with the same name still mean what they did in earlier years.

Newly eligible hospitals identified on the most current ASA ASDB, and confirmed for having a 24‑hour ED, are provided the opportunity to be selected into the sample on the basis of the sampling fraction of the stratum in which each newly eligible hospital is located.

4.4.3 Weights and adjustments

Each year, weights and adjustments are calculated and applied to the collected data to ensure that the survey results represent the target population. Sampling weights are first calculated as the inverse of the probability of selection and then adjusted for variable nonresponse by a procedure known as poststratification, or benchmark adjustment. For steps involving within-hospital adjustments, the processing is carried out at the facility/month level; that is, adjustments are made to data for each month within each facility within each hospital. The derivation of weights to adjust for unequal POS, nonresponse, and other sources of bias is processed at the hospital/stratum/region level.

Probabilities of selection. DAWN hospitals are selected using stratified simple random sampling with oversampling in DAWN metropolitan areas. A hospital can have up to three POSs: a remainder-level POS, a division-level POS, and an OS area–level POS (see Section 4.1.3). Decisions about which POS to use are made after an analysis of response rate and nonresponse bias is conducted for each OS area.

Within-hospital weighting adjustment. Charts may be intentionally sampled, or there may be unintentional gaps due to problems in collecting data or obtaining access to records (see Section 4.2.2). To compensate for within-hospital nonresponse, the DAWN weighting plan includes a nonresponse adjustment factor for each month of data collection within each facility; it is equal to the number of ED visits divided by the number of charts reviewed for each of 12 months in the data collection year. The within-hospital weights are applied to the by-month count of visits. That is, the visit counts for a given facility/month are first summed for each drug and then multiplied by the corresponding within-hospital adjustment factor for that facility/month. The weighted totals are then summed over all facilities and months to give a total weighted visit count for each drug for each hospital.

Weighting adjustment for hospital nonresponse. Hospital-level nonresponse occurs when hospitals fail to provide valid data for at least 3 months of the data collection year. To minimize the impact of hospital nonresponse, the DAWN weighting plan includes nonresponse adjustment factors that are developed and applied within each weighting class. Weighting classes are formed on the basis of the aforementioned sampling stratification schemes. Within each weighting class, the nonresponse adjustment factor is calculated as the sum of the sampled hospital weights divided by the sum of the weights of the responding hospitals. The hospital nonresponse adjustment factors are checked to make sure the adjustments are within reasonable bounds. If a nonresponse adjustment factor is too large, adjacent weighting classes are collapsed, and new nonresponse adjustment factors are calculated.

When the hospital-level nonresponse adjustment factors are finalized, a nonresponse-adjusted sampling weight is then calculated as the product of the nonresponse adjustment factor and the sampling weight. For each weighting class, a verification check is conducted to ensure that the sum of the nonresponse-adjusted sampling weights is equal to the sum of the sampled hospital weights.

Weighting adjustment for population benchmarks (poststratification). The DAWN weighting plan also includes a poststratification adjustment factor that reconciles the weighted number of total visits for responding hospitals with the number of total visits from the most recent AHA ASDB. DAWN uses a ratio adjustment within strata to implement this adjustment.

Within each stratum, the adjustment factor is calculated as the ratio of the AHA count of total visits to the weighted sum of total visits for responding hospitals. The factors are verified to ensure they are within reasonable bounds. If they are out of bounds (either too small or too large), adjacent poststratification strata are collapsed, and new poststratification adjustment factors are calculated.

When the poststratification adjustment factors are finalized, a poststratified weight is then calculated. The final weight is calculated as the product of the poststratification adjustment factor and the nonresponse-adjusted sampling weight. For each poststratification stratum, a validity check is conducted to ensure that the sum of the poststratified weighted total visits is equal to the corresponding AHA count of total visits from each stratum.

Estimates for the entire universe of DAWN-eligible hospitals in the United States are produced by applying poststratified weights to the data received from the sampled hospitals.

4.4.4 Sequential process of developing and applying weights and adjustments

The order of processing the weights and adjustments is as follows:

  1. Identify the design strata. Variance estimation strata are formed on the same basis as the design strata, where selected strata are collapsed to ensure that there are at least two hospitals in each estimation stratum.
  2. Compute hospital-level, design-based weights on the basis of design-based selection probabilities.
  3. Apply an initial weight adjustment to correct for minor discrepancies in the selection probabilities.
  4. Define variance estimation strata.
  5. Define weighting classes that are sufficiently large and internally homogeneous for nonresponse adjustment. These usually are combinations of variance estimation strata.
  6. Compute nonresponse adjustments within weighting class.
  7. Define poststratification classes (may be similar to nonresponse weighting classes).
  8. Compute poststratification adjustment factors on the basis of reported visits for responding hospitals and poststratum totals from the AHA frame.
  9. Prepare an output file with each of the hospital-level weights and weight adjustment factors listed individually for quality control (QC) review.
  10. Compute the final case weights.
  11. Conduct QC of weights.
  12. Perform QC review.

5. DAWN PUBLICATIONS AND DATA DISSEMINATION

DAWN issues both regular and ad hoc reports, tables, and related data products. In addition, DAWN PUFs are available on the SAMHDA Web site. This section describes the characteristics of these data products and the standards DAWN uses to compile data, present estimates, and produce data files.

5.1 Analytic groups

For the purpose of analysis, DAWN developed a set of categories to use when reporting on ED visits. Referred to as "analytic groups," these categories combine visits with similar characteristics to produce summary statistics. The DAWN analytic groups and their definitions are provided in Table 4. The analytic groups fall into one of three types: all visits (regardless of intent), visits where there is an indication of some type of drug misuse or abuse, and visits where there is no indication of misuse or abuse.

Because of DAWN's focus on drug misuse and abuse, this topic is addressed by several analytic groups, including all drug misuse or abuse, all visits involving illicit drugs, visits involving nonmedical use of pharmaceuticals, visits involving alcohol for patients of all ages, and visits involving alcohol for patients under the age of 21. Also isolated for analysis are visits involving drug-related suicide attempts and visits made by patients seeking detoxification services. The subgroups under "All Misuse and Abuse" in Table 4 are not mutually exclusive because a single visit can involve multiple types of drugs. For example, an ED visit involving marijuana and oxycodone would be grouped with other visits involving illicit drugs, as well as with visits involving nonmedical use of pharmaceuticals.

Annually, DAWN produces comprehensive sets of tables, the DAWN Trend Tables, that provide estimates and rates of drug-related ED visits by type of drug, patient sex and age, visit disposition, and other characteristics; each table includes estimates and rates for the current year and all prior years. A complete set of tables is produced for each analytic group listed in Table 4. Each set is reproduced for the Nation and for metropolitan areas with sufficiently high levels of participation (see Table 1). A more detailed description of the DAWN Trend Tables is provided in the Guide to the DAWN Trend Tables.22

Table 4. DAWN analytic groups
Analytic group Description
All Visits This group includes all visits that are reportable to DAWN without regard for the reason for the visit or the specific drugs involved. It includes visits involving all forms of drug misuse or abuse plus visits resulting from adverse reaction, accidental ingestion, suicide attempts, and visits where patients were seeking detoxification services. These estimates are useful for looking at overall levels of drug involvement in ED visits.
    — Drug-related ED visits that involve drug misuse or abuse
All Misuse and Abuse This analytic category includes visits that involve all forms of drug misuse or abuse as defined by DAWN. This is the combination of visits from the following four analytic groups: illicit drug visits, nonmedical use of pharmaceuticals, alcohol-related visits, and underage drinking. A visit may appear in more than one of those subgroups, but it will appear only once in this overall group. Suicide-attempt visits and seeking detox visits will be included in this category if illicit drugs were involved.
Illicits (excluding alcohol) This analytic category includes visits that involve the use of drugs that have limited or no therapeutic value and are generally illegal if taken without a prescription. These substances include cocaine, heroin, marijuana, synthetic cannabinoids, amphetamines, methamphetamine, MDMA (Ecstasy), GHB (gamma-hydroxybutyric acid), flunitrazepam (Rohypnol®), ketamine, LSD, PCP, and hallucinogens. Visits involving the inhalation of substances for their psychotherapeutic properties (e.g., sniffing model airplane glue) are included.
Nonmedical Use of Pharmaceuticals This analytic category includes visits that involve nonmedical use of pharmaceuticals: patients who took a higher than prescribed or recommended dose of their own medication, patients who took a pharmaceutical prescribed for another person, malicious poisoning of the patient by another individual, and documented substance abuse involving pharmaceuticals.
All Alcohol This analytic category includes ED visits involving alcohol. For adults aged 21 and older, the alcohol was found in combination with other drugs. For patients under the age of 21, the visit may involve alcohol alone or in combination with other drugs.
Underage Drinking This analytic category includes ED visits that involve alcohol use (alone or with other drugs) for patients under the age of 21. Underage drinking is an important barometer of adolescent drinking patterns and a predictor of more serious substance abuse problems in young adults.
Suicide Attempts This analytic category includes ED visits that involve drug-related suicide attempts. It includes visits for drug overdoses, as well as suicide attempts by other means (e.g., using a firearm) if drugs were involved or related to the suicide attempt. Inclusion in this analytic category has no restrictions on the type of drug used.
Seeking Detox This analytic category includes nonemergency requests made through the ED for admission to detoxification unit, visits to obtain medical clearance before being incarcerated, and acute emergencies where an individual is experiencing withdrawal symptoms and requests detox. These estimates do not include patients who seek or enter the hospital's detox unit through other avenues.
    — Drug-related ED visits that do NOT involve drug misuse or abuse
Adverse Reactions This analytic category includes ED visits in which an adverse health consequence (e.g., side effects or an allergic reaction) resulted when taking prescription drugs, over-the-counter medications, or dietary supplements as prescribed or recommended.
Accidental Ingestions This analytic category includes ED visits in which an individual accidentally or unknowingly used a prescription drug, over-the-counter medication, or dietary supplement. Drug-related accidental ingestion typically involves patients aged 5 and under.

5.2 Drug lists

In addition to being a coding system that accommodates different levels of drug detail, the DAWN DRV provides a method for aggregating drugs into meaningful, higher-level groupings. DAWN currently collects drug information on thousands of individual products. The individual products are mapped to their generic drug name; currently, DAWN reports on approximately 3,300 generic drugs. The DAWN Trend Tables provide estimates and rates using a shorter list of approximately 500 drugs, known as the "standard drug list." The tables in the DAWN ED Annual Reports highlight approximately 100 drugs selected from the standard drug list.

5.3  Estimates of visits versus drugs

All estimates provided in DAWN publications and tables are calculated using data that have been weighted as described in Section 4.4. Estimates for any variable of interest are determined by first summing the case totals within facility/month, applying the within-hospital weight, summing to the hospital level, applying the final hospital weight, and summing over all hospitals.

The DAWN ED Annual Reports, short reports, and the DAWN Trend Tables include predominantly estimates at the ED visit level—that is, how many visits involved a certain drug. Another measure is the total number of drugs reported. Because most ED visits involve more than one drug, the total drug reports will always exceed the total drug-related ED visits. To illustrate the difference, consider a visit involving oxycodone and aspirin. Both drugs are pain relievers. This visit will count as one visit involving oxycodone and one visit involving aspirin. When reporting the number of visits involving pain relievers in general, this visit will be counted just once even though two types of pain relievers were involved.

5.4 Standardized rates

DAWN ED Annual Reports and the DAWN Trend Tables include population-based rates as well as estimates. Rates are standardized measures that are helpful when comparing levels of drug-related ED visits for different years, types of visits, and demographic groups. DAWN rates for years and types of visits are based on the whole population; for example, there were 790.4 ED visits involving drug misuse or abuse per 100,000 population in 2011 compared with 552.9 visits in 2004. For specific age groups and sexes, the denominator is limited to the population in that age group or sex. For age in particular, rates are important because the size of the underlying population differs considerably across DAWN age groups (see Section 3.4.1). For example, in 2011, there were 13.5 million individuals aged 18 to 20 in the United States and 40.6 million aged 35 to 44. Accordingly, the estimated number of ED visits involving drug misuse or abuse was 239,281 visits for those aged 18 to 20 and 432,957 visits for those aged 35 to 44. To allow comparison between the two age groups, standardized rates are calculated as the number of ED visits per 100,000 persons in that age group. In this example, while the estimated number of visits was much lower for persons aged 18 to 20, the rate of visits was substantially higher: 1,771.5 for persons aged 18 to 20 compared with 1,065.7 visits for persons aged 35 to 44. Because they are reported as percentages, the RSEs provided in DAWN tables apply equally to the estimates and the rates.

5.5 Population estimates used to calculate rates

The U.S. Census Bureau issues population estimates for each decennial year. Each year between decennials, estimates for the current year as well as estimates for all years since the last decennial are reissued. Each year's reissued estimates are referred to as "Vintage 20xx." Every reporting year, DAWN recalculates rates for all years (2004 through current data collection year) using the most recent census population estimates for all data collection years.23 For DAWN reporting years 2004–2009, the population data were based on the 2000 decennial census. For DAWN reporting years 2010 and 2011, population counts were based on the 2010 decennial census. Population estimates used to generate DAWN rates are as of July in the data collection year as reported in the Postcensal Resident Population National Population Dataset, National Estimates by Demographic Characteristics—Single Year of Age, Sex, Race, and Hispanic Origin, Monthly Population Estimates series. Estimates at the metropolitan area level were drawn from the Postcensal Resident Population County Population Datasets, County Estimates by Demographic Characteristics—Age, Sex, Race, and Hispanic Origin, State Datasets series.

The 2011 DAWN data series included estimates and rates for 2004–2011. The estimates and rates for 2004–2010 that were issued as part of the 2011 series replaced previously issued estimates and rates for those years. As a matter of record, the 2004–2010 DAWN data issued as part of the DAWN 2010 series used a different method for estimating population because Vintage estimates for 2010 were not available at the time of publication of the 2010 DAWN data series. This methodology is described in the DAWN Methodology Report, 2010 Update.

5.6 Measures of precision and error

Each hospital in the DAWN sample was selected through a random process, which theoretically could have been repeated many times, resulting in many hypothetical samples. Sampling error refers to the extent to which these samples vary. Two measures of this variability are the SE and the RSE, which is defined as the SE of the estimate divided by the estimate itself. The precision of an estimate is inversely related to the sampling variance, as measured by the RSE. The greater the RSE value, the lower the precision.

For example, if 10,000 estimated visits involve a given drug, and this estimate has an SE of 500 visits, then the RSE value is 5 percent:

RSE = SE/Estimate
RSE = 500/10,000
RSE = 0.050
RSE% = 5.0% (RSE × 100%).

In addition to RSEs, confidence intervals (CIs) are often included in tables published by DAWN. The 95 percent CI is calculated as

CI = Estimate ± (1.96 × RSE × Estimate),

where 1.96 comes from the table of normal distribution z-values and means that 95 percent of the normal distribution lies within 1.96 standard deviations of the mean.

Applying the formula to the example above, the 95 percent CI would be

10,000 ± (1.96 × 0.05 × 10,000) = 10,000 ± 980.0
Lower limit: 10,000 − 980 = 9,020
Upper limit: 10,000 + 980 = 10,980
95% CI: 9,020 to 10,980.

If repeated samples were drawn from the same population of hospitals, using the same sampling and data collection procedures, then 95 percent of the time the true population values would fall between 9,020 and 10,980.

Both between- and within-hospital variance components are accounted for in the variance estimation process. Within-hospital variance is estimated using a replication strategy by which two random replicates are created within each hospital, and the variance between the two replicates represents the within-hospital contribution. Typically, this component is considerably smaller than the between-hospital variance, which is calculated as the variance between weighted hospital totals within each stratum.

Variance estimates reported in the DAWN Trend Tables are determined using the Taylor series linearization variance estimation method available in SUDAAN® software. This method is particularly appropriate for analyzing cluster data, such as those that are generated by the DAWN sampling plan.

5.7 Suppression

DAWN uses a set of criteria to determine whether estimates can be released to the public. Data may be suppressed to protect patient confidentiality or to ensure that published findings meet statistical standards of reliability for survey results. In all published materials, estimates are suppressed according to the following rules:

It is mathematically possible that an estimate could have no sampling error and an RSE of zero. This occurs when the number of ED visits being estimated is small, all the hospitals contributing to that estimate were selected with certainty, and the absence of any sampled hospital is due to nonresponse. In most cases, an estimate with an RSE of zero is suppressed on the basis of the small number of cases. In the unlikely event that an estimate is published with an RSE of zero, it is most appropriate to interpret the RSE as signifying that the necessary data were not available to approximate the sampling error.

5.8 Cross-year comparisons

In DAWN ED Annual Reports and the DAWN Trend Tables, comparisons in the estimates of ED visits between years are presented in the form of percentage differences, calculated as the current estimate minus an earlier year's estimate divided by that estimate. For shorter-term comparisons, percent changes are calculated for the current year compared with last year and the current year compared with 2 years ago. For longer-term comparisons, estimates for the current year are compared with those for 2004.24 The percent change is reported only if the difference is statistically significant at the p < 0.05 level.

Tests for the significance of differences between two years' estimates consider the variance of each year's estimate and the covariance between the two. Hospitals that appear in both samples and provide data in both years will contribute to the covariance and thus decrease the overall sampling variance beyond the combined contribution of the two samples. That is, the variance estimation process used to establish significance takes into account any overlap between hospitals that participated in both years.

5.9 DAWN public use files

SAMHDA has primary responsibility for the collection, analysis, and dissemination of behavioral health data collected by SAMHSA. SAMHDA promotes the access and use of SAMHSA's substance abuse and mental health data by providing public-use data files and documentation for download and online analysis tools to support a better understanding of this critical area of public health. DAWN data are made available at the SAMHDA site as soon as the data are released by SAMHSA. Data are available in the following formats: SPSS, SAS, Stata, ASCII, and tab delimited. PDF and HTML codebooks are available online for all years.

Activities and services SAMHDA performs in support of public-use versions of data and documentation include the following:

The SAMHDA Web site was first published on December 3, 1997. The University of Michigan's Inter-University Consortium for Political and Social Research is under contract to CBHSQ to disseminate data and to maintain the SAMHDA Web site and bibliography of publications.

6. QUALITY ASSURANCE/QUALITY CONTROL

Survey error, also referred to as bias, is the extent to which findings from the survey sample differ from those of the population of interest. Error can be introduced at any stage in the survey process, from building the sample frame to reporting estimates. This section documents methodologies employed by DAWN to help ensure that published estimates are representative, accurate, and reliable.

6.1 Minimization of nonsampling error

To control the nonsampling error components and produce data of high quality, DAWN has a well-defined and ongoing data quality assurance (QA) and data quality control (QC) program. The two primary components of the data QA/QC program are (a) the extensive and continuous monitoring of data quality during data collection and processing, and (b) annually, an intensive review of the monthly data for each ED in relation to other months for the current and all prior reporting years.

6.1.1 Maintaining data quality during data collection and data preparation

Measures used to monitor data quality during data collection include but are not limited to onsite quality audit reviews and quarterly standardized error feedback reports. In addition to those measures, DAWN employs a custom-built software system (eHERS) to collect DAWN data. eHERS, which provides automated prompts to ensure that DAWN Reporters collect complete data, is populated with the most current detailed codes for drugs, race/ethnicity, visit disposition, and other categorical variables. It performs real-time data validation checks to ensure that the data are within valid ranges and consistent with other information collected for the visit. eHERS also checks across visits to ensure that visits are not entered multiple times and follows a procedure to resolve conflicts if multiple entries are detected.

6.1.2 End-of-year data quality review

Before data are weighted, researchers responsible for the collection (the DAWN operations contractor) and analysis (data analysis contractor) of DAWN data meet with staff from CBHSQ to review the quality of the data. This process is referred to as the data quality review (DQR).

Before the DQR meeting, the DAWN operations contractor prepares an electronic file that summarizes what is known about the quality of the data that was collected in the prior year. The DQR spreadsheet contains descriptive information including facility ID, facility name, oversampled area name, stratum, eligibility, subsampling information, and participation status. In addition, the DQR spreadsheet includes summary data for each of the fields for each ED by month, as shown in Table 5. Review of these data items reveals what portion of ED visits in each hospital for each month were evaluated for inclusion in DAWN. Depending on the pattern of missing data for an ED, the review committee comes to a consensus about whether to delete, adjust, or impute the count of eligible ED visits, the count of medical charts reviewed, and the count of identified DAWN cases in each ED for each month of the reporting year. These counts are vital to developing accurate within-facility adjustment factors for each month for each facility.

Table 5. Data items in the data quality review spreadsheet
Field Month 1 Month 2 Month 12
Visits
Charts
Cases
Cases/charts
Subsampling rate
Left without being seen
Delete code
Adjust code
Impute code
Hard delete code
Donor code

6.2 Minimization of sampling error

The statistical methodologies described in Section 4.4 reflect efforts to minimize sampling error. For example, the DAWN statistical methodology provides for clearly defined criteria to construct the initial hospital sampling frame. Coverage error is minimized by using a sampling frame that has virtually 100 percent coverage of the target population. Weighting is introduced to account for the probability of selection, within-hospital nonresponse, hospital-level nonresponse, and the total number of visits in the sample frame as independently established by the AHA ASDB. Validity checks are made at each stage of weighting to ensure that the sum of weights at that stage equaled the relevant reference point.

6.3 Quality control on released reports and tables

All publications and tables issued by DAWN are subject to multitiered data QC measures. Tables are produced and independently verified by a separate statistician/programmer. Estimates are verified against other tables to ensure cross-table consistencies. Estimates for different years are verified against each other to ensure cross-year consistencies. Tables in reports are verified against source files. Text descriptions of findings are verified against report tables by three separate and independent readers. All observations in respect to the similarity or differences between estimates are established through statistical testing that is independently recomputed and verified.

7. DATA LIMITATIONS

7.1 Limitations of survey data

Information on drug-related ED visits in DAWN is based on a sample and is, therefore, subject to sampling variability. The SE measurements and CIs provided for all estimates reflect the sampling variability that occurs (a) by chance because only a sample rather than the entire universe is surveyed, and (b) by nonresponse. As in any survey, nonresponse is of concern because it creates larger-than-expected sampling errors plus the opportunity for unpredictable biases. DAWN addresses these issues in the short term by always reporting SEs based on the actual sample of respondents and for the long term by continuing its efforts to raise the hospital participation rate.

7.2 Limitations of using extant medical records

Although every effort is made during the data collection phase to collect data accurately and precisely, extant medical records vary in specificity and detail. Factors that may affect the reliability and accuracy of the findings include the following:

7.3 Limitations on toxicology test finding

Although DAWN documents whether a drug was positively confirmed by toxicology testing, DAWN does not require that all drugs reported for the ED visit be confirmed by laboratory testing. Toxicology tests are not used consistently across EDs, and some toxicology tests are not specific enough to identify particular drugs. Furthermore, a positive toxicology test is not necessarily evidence of recent drug involvement in an ED visit if it is a current medication or a drug that persists in the system long after it was used. For this reason, DAWN requires that the involvement of drugs be mentioned in the ED record, not just in the toxicology testing results, for the visit to be considered a DAWN case.

8. HISTORY OF DAWN, 1970–2012

DAWN is a public health surveillance system that has monitored drug-related ED visits to hospitals since the early 1970s. DAWN was initially established by the U.S. Drug Enforcement Administration. DAWN was transferred to the U.S. Department of Health and Human Services (HHS) in 1980. Within HHS, the National Institute on Drug Abuse (NIDA) conducted DAWN from 1980 to 1992. For the period 1992 through 2011, CBHSQ (formerly the Office of Applied Studies) of SAMHSA was responsible for DAWN operations and reporting. CBHSQ ceased performing DAWN data collection as of the end of calendar year 2011, and the responsibility for collection of data on drug-related ED visits was passed to the National Center for Health Statistics (NCHS). NCHS incorporated DAWN data elements into the National Hospital Care Survey (NHCS). NCHS is observing DAWN conventions and methodologies to the greatest extent possible so that data collected via DAWN for the years 2004–2011 can be compared with the data collected by the NHCS for later years. For example, given its sample design and size, the drug-related ED visits data collected through NHCS will be representative of the nation but not the DAWN metropolitan areas. Additional information on NHCS and its collection of information on drug-related ED visits is available at the NHCS Web site.25

Since its inception, DAWN has relied on data collected from a sample of hospitals. However, over the years, the exact survey methodology has been adjusted to improve the quality, reliability, and generalizability of the information produced by DAWN. When NIDA assumed responsibility for DAWN in 1980, implementation of a sample of hospitals to produce representative estimates for the Nation and for selected metropolitan areas became a priority. This sample, refreshed with annual maintenance, continued to support DAWN estimates for the contiguous United States and 21 metropolitan areas until 2002. Major population shifts and changes in the hospital industry between 1980 and 2002 made apparent the need for a redesign of the sample of hospitals. Many other features of DAWN (e.g., definition of a DAWN visit to include all drug-related medical emergencies and not merely those involving misuse or abuse) were also introduced at that time.26

In the redesign in 2003, DAWN's goal remained to produce national as well as metropolitan area–level estimates. Retention of the original 21 metropolitan areas was important because of the ongoing demand for DAWN estimates by public health professionals in those areas. In addition, inclusion of major population centers in each of the nine census divisions was deemed important to improve DAWN's geographic and population coverage. A total of 48 metropolitan areas was identified for inclusion in DAWN. The composition of these metropolitan areas was based on the definitions issued by the Office of Management and Budget (OMB) in June 2003. For consistency, DAWN has maintained the 2003 definitions, even if counties were added in subsequent years.

Between 1980 and 2003, OMB had substantially enlarged the coverage areas for 4 of the original 21 metropolitan areas. Users of DAWN statistics in these 4 areas—Los Angeles, Miami, New York, and San Francisco—remained interested in obtaining estimates for the areas covered by the original 21 metropolitan areas. To address the needs of these users, DAWN subdivided these metropolitan areas according to their earlier composition and planned oversamples in the subdivided portions. That is, for each of these areas, there were an oversample for the metropolitan area as defined in 2003 and also additional oversampling in the submetropolitan areas. When participation is high enough, separate estimates are made for the submetropolitan areas as well as the entire metropolitan area.

In 2000, DAWN adopted the Multum Lexicon, © 2012, a drug vocabulary and classification tool developed and maintained by Lexi-Comp, Inc., a private firm that distributes the Lexicon and regular updates through its Web site. While the use of the Lexicon is free of charge, a licensing agreement specifies the terms required of users. In accordance with the licensing agreement, DAWN publications, tabulations, and software applications cite the Multum Lexicon as the source and basis for the system DAWN uses to code drugs.

The DAWN survey relies on a longitudinal probability sample of hospitals located throughout the United States. To be eligible for selection into the DAWN sample, a hospital must be a non-Federal, short-stay, general surgical and medical hospital located in the United States, with at least one 24-hour ED. This sampling strategy was first implemented in the 2004 data collection year and has been followed since that year.

End Notes

1 DAWN documents can be found on the DAWN Web site, http://www.samhsa.gov/data/DAWN.aspx.
2 DAWN draws a systematic sample of eligible charts to review.
3 Not all hospitals reporting to DAWN are part of the current sample. These hospitals' data are provided to them for local use. Therefore, the number of drug-related ED visits used in estimation is smaller than the total number identified.
4 Drug-related visits are defined by DAWN as any ED visit related to recent drug use. Additional detail on DAWN's definition of drug-related visits is provided in Section 3.2.
5 DAWN documents can be found on the DAWN Web site at http://www.samhsa.gov/data/DAWN.aspx.
6 Guide to the DAWN Trend Tables is available as an attachment to the DAWN ED Annual Reports and as a freestanding document at the DAWN Web site.
7 DAWN data can be found on the SAMHDA Web site at http://www.icpsr.umich.edu/icpsrweb/SAMHDA/.
8 DAWN Reporters are responsible for reviewing ED visit records, deciding if a visit is eligible for DAWN, and, if so, recording select data items for the visit. Additional information on collection of DAWN data is provided in Section 3.2.
9 The 2007–2011 ED Reference Guide is available at the DAWN Web site (http://www.samhsa.gov/data/DAWN.aspx).
10 Alcohol use by a minor with no other drug involvement is eligible for DAWN. Alcohol use by an adult must be accompanied by another drug to be eligible for DAWN.
11 To be reportable as an illicit drug, a nonpharmaceutical substance must be intentionally consumed by inhalation, sniffing, or snorting, and it must have a psychoactive effect when inhaled. Carbon monoxide is excluded from the inhalants. Cases involving accidental exposures to inhalants (e.g., exposure to paint fumes while one is painting a closet) are excluded.
12 DAWN documents can be found on the DAWN Web site (http://www.samhsa.gov/data/dawn/MultumLicenseAgreement.pdf).
13 These files and DRV documentation are available at the DAWN Web site at http://www.samhsa.gov/data/dawn/DRV/Drug%20Reference%20Vocabulary.zip.
14 This code may be applied if the inpatient unit was not specified or does not match one of the preceding units. Also included herein are "combo" units, e.g., a unit that offers both psychiatric and detox services.
15 The redesign of the DAWN ED component is described in detail in DAWN: Development of a New Design, which is available at the DAWN Web site (http://www.samhsa.gov/data/DAWN.aspx).
16 The 24-hour status of hospitals is not contained on the AHA file and is determined by contacting otherwise eligible hospitals directly.
17 Hospitals in the four MSAs with submetropolitan area oversampling can have up to three nonzero POS/strata: (a) POS/stratum for membership in the MSA, (b) POS/stratum for membership in the submetropolitan area, and (c) POS/stratum for membership in the remainder area.
18 In DAWN metropolitan areas, size categories were determined independently for each OS area. The number of hospitals determined the unique size categories: fewer than four hospitals were placed in one size category; four to seven hospitals were placed in two size categories; and eight or more hospitals were placed in four size categories. Areas outside of DAWN metropolitan areas were organized into three size categories.
19 The 2007–2011 ED Reference Guide is available at the DAWN Web site (http://www.samhsa.gov/data/DAWN.aspx).
20 This version of the annual data is referred to as the "microdata" because it includes one record for every brand of drug mentioned in a visit. There are up to 22 records for each visit.
21 Identical drug IDs can result when different brand codes map to the same drug ID. When the duplicate drug ID is removed, the brand code associated with it will be lost because only one brand is retained for each unique drug ID in the visit-level file. The detailed information on all brands is retained in the brand-level file and can be retrieved, if needed.
22 The Guide to the DAWN Trend Tables is available as an attachment to the DAWN ED Annual Reports and as a freestanding document at the DAWN Web site (http://www.samhsa.gov/data/DAWN.aspx).
23 The most current population estimates for earlier years (e.g., population estimates for 2004 that were issued in 2010) may be different than those issued earlier (e.g., population estimates for 2004 that were issued in 2009). The most currently issued population estimates are used in DAWN rate calculations, and the newly calculated rates replace previously published rates. Differences in the rates at the national level are usually insignificant, but differences at the metropolitan area level may be larger and more noticeable.
24 Due to data limitations in 2004, long-term comparisons for ED visits resulting from adverse reactions are made between 2005 and the current year.
25 Further information on NHCS and its data are available at http://www.cdc.gov/nchs/nhcs.htm.
26 Additional detail on the 2003 redesign is available in the following publication: Substance Abuse and Mental Health Services Administration, Center for Behavioral Health Statistics and Quality. (2002). Drug Abuse Warning Network: Development of a new design (methodology report) (DAWN Series M-4, DHHS Publication No. SMA 02-3754). Rockville, MD: Author.



Attachment C

Guide to Drug Abuse Warning Network Trend Tables,
2011 Update


U.S. DEPARTMENT OF HEALTH AND HUMAN SERVICES
Substance Abuse and Mental Health Services Administration
Center for Behavioral Health Statistics and Quality

ACKNOWLEDGMENTS

This report was prepared by the Center for Behavioral Health Statistics and Quality (CBHSQ), Substance Abuse and Mental Health Services Administration (SAMHSA), U.S. Department of Health and Human Services (HHS), and by RTI International (a trade name of Research Triangle Institute, Research Triangle Park, NC). Work by RTI was performed under Contract No. HHSS283200700002I.

PUBLIC DOMAIN NOTICE

All material appearing in this publication is in the public domain and may be reproduced or copied without permission from SAMHSA. Citation of the source is appreciated. However, this publication may not be reproduced or distributed for a fee without the specific, written authorization of the Office of Communications, SAMHSA, HHS.

RECOMMENDED CITATION

Center for Behavioral Health Statistics and Quality (2013). Guide to DAWN Trend Tables, 2011 Update. Rockville, MD: Substance Abuse and Mental Health Services Administration.

ELECTRONIC ACCESS

This publication may be downloaded from http://store.samhsa.gov. Or please call SAMHSA at

1-877-SAMHSA-7 (1-877-726-4727)
(English and Español).

ORIGINATING OFFICE

Center for Behavioral Health Statistics and Quality
Substance Abuse and Mental Health Services Administration
1 Choke Cherry Road, Rockville, MD 20857

May 2013



CONTENTS

1. Major features of DAWN Trend Tables, 2011 Update
1.1 Analytic groups
1.2 Workbooks containing national estimates
1.3 Workbooks containing metropolitan area estimates
1.4 Information organization and format
1.5 Special note on age categories

2. Values reported in DAWN Trend Tables
2.1 Weighted annual estimates
2.2 Rates per 100,000 population
2.3 Relative standard error (%)
2.4 Percent change (p < 0.05)
2.5 Lower and upper 95 percent confidence limit on weighted annual estimate
2.6 Suppression

List of Tables

Table 1. DAWN analytic groups
Table 2. Workbook names for national estimates
Table 3. Workbook names for metropolitan areas and divisions
Table 4. Tables in each workbook of the DAWN Trend Tables

1. MAJOR FEATURES OF DAWN TREND TABLES, 2011 UPDATE

Drug Abuse Warning Network (DAWN) Trend Tables provide estimates of drug-related visits to hospital emergency departments (EDs) for different groups of patients, different years, and different geographic locations. Each year DAWN produces an updated set of DAWN Trend Tables that includes data for 2004 through the current year. The DAWN Trend Tables, 2011 Update, includes 120 Microsoft Excel workbooks: 10 workbooks contain estimates for the Nation, and the same 10 workbooks are repeated for each of 11 metropolitan areas. Each workbook contains 56 tables (1 table per worksheet). Each table presents data for 2004, 2005, 2006, 2007, 2008, 2009, 2010, and 2011. This document is intended to help DAWN users find the workbooks, tables, and estimates of interest to them.

Further information about DAWN is available at the DAWN website, including detail on the DAWN data program and the methodologies used to collect, process, and report DAWN data.1 Information on other sources of data on substance abuse and mental health from the Center for Behavioral Health Statistics and Quality is located at http://www.samhsa.gov/data/.

1.1 Analytic groups

DAWN analytic groups represent different groupings of visits that were developed to meet the data needs of a range of audiences. The DAWN analytic groups and their definitions are provided in Table 1.

1.2 Workbooks containing national estimates

Workbook names have three parts: a prefix that describes the geographic coverage of the workbook, a middle term that reflects the latest year of the data, and a suffix that describes the analytic group. Table 2 lists the workbook names for the 10 workbooks containing estimates for the Nation. Each worksheet contains data for 2004 through 2011.2

Table 1. DAWN analytic groups
Analytic group Description
All Visits This group includes all visits that are reportable to DAWN without regard for the reason for the visit or the specific drugs involved. It includes visits involving all forms of drug misuse or abuse plus visits resulting from adverse reaction, accidental ingestion, suicide attempts, and visits where patients were seeking detoxification services. These estimates are useful for looking at overall levels of drug involvement in ED visits.
Drug-related ED visits that involve drug misuse or abuse
All Misuse and Abuse This analytic category includes visits that involve all forms of drug misuse or abuse, as defined by DAWN. This category is the combination of visits from the following four analytic groups: illicit drug visits, nonmedical use of pharmaceuticals, alcohol-related visits, and underage drinking. A visit may appear in more than one of the subgroups listed below, but it will appear only once in this overall group. Suicide attempt visits and seeking detox visits will be included in this category if illicit drugs were involved.
Illicits (excluding alcohol) This analytic category includes visits that involve the use of drugs that have limited or no therapeutic value and are generally illegal if taken without a prescription. These substances include cocaine, heroin, marijuana, synthetic cannabinoids, amphetamines, methamphetamine, MDMA (Ecstasy), GHB (gamma-hydroxybutyric acid), flunitrazepam (Rohypnol®), ketamine, LSD, PCP, and hallucinogens. Visits involving the inhalation of substances for their psychoactive properties (e.g., sniffing model airplane glue) are included.
Nonmedical Use of Pharmaceuticals This analytic category includes ED visits that involve nonmedical use of pharmaceuticals: patients who took a higher than prescribed or recommended dose of their own medication, patients who took a pharmaceutical prescribed for another person, malicious poisoning of the patient by another individual, and documented substance abuse involving pharmaceuticals.
All Alcohol This analytic category includes ED visits involving alcohol. For adults aged 21 and older, the alcohol was found in combination with other drugs. For patients under the age of 21, the visit may involve alcohol alone or in combination with other drugs.
Underage Drinking This analytic category includes ED visits that involve alcohol use (alone or with other drugs) for patients under the age of 21. Underage drinking is an important barometer of adolescent drinking patterns and a predictor of more serious substance abuse problems in young adults.
Suicide Attempts This analytic category includes ED visits that involve drug-related suicide attempts. It includes visits for drug overdoses and for suicide attempts by other means (e.g., using a firearm) if drugs were involved or related to the suicide attempt. Inclusion in this analytic category has no restrictions on the type of drug used.
Seeking Detox This analytic category includes nonemergency requests made through the ED for admission to detoxification unit, visits to obtain medical clearance before being incarcerated, and acute emergencies where an individual is experiencing withdrawal symptoms and requests detox. These estimates do not include patients who seek or enter the hospital's detox unit through other avenues.
Drug-related ED visits that do NOT involve drug misuse or abuse
Adverse Reactions This analytic category includes ED visits in which an adverse health consequence (e.g., side effects or an allergic reaction) resulted when taking prescription drugs, over-the-counter medications, or dietary supplements as prescribed or recommended.
Accidental Ingestions This analytic category includes ED visits in which an individual accidentally or unknowingly used or was administered a prescription drug, over-the-counter medication, or dietary supplement. Drug-related accidental ingestion typically involves patients aged 5 and under.
Table 2. Workbook names for national estimates
Analytic group Abbreviated analytic group name Workbook name for file with national estimates
All Misuse and Abuse AllMA Nation_2011_AllMA.xls
Illicits (excluding alcohol) Illicit Nation_2011_Illicit.xls
Nonmedical Use of Pharmaceuticals NMUP Nation_2011_NMUP.xls
All Alcohol Alcohol Nation_2011_Alcohol.xls
Underage Drinking Underage Nation_2011_Underage.xls
Suicide Attempts Suicide Nation_2011_Suicide.xls
Seeking Detox Detox Nation_2011_Detox.xls
Adverse Reactions Adverse Nation_2011_Adverse.xls
Accidental Ingestions Accidental Nation_2011_Accidental.xls
All Visits All Nation_2011_All.xls

1.3 Workbooks containing metropolitan area estimates

DAWN prepares estimates each year for DAWN metropolitan areas that have sufficient participation to support estimates with acceptable reliability and precision. Table 3 lists the names of workbooks containing estimates for metropolitan areas and divisions. For example, the workbook containing national estimates for ED visits involving all drug misuse or abuse is named "Nation_2011_AllMA.xls." The workbook with parallel estimates for Boston is named "Boston_2011_AllMA.xls." Each of the 11 geographic areas listed in Table 3 has a set of 10 Excel workbooks, one workbook for each analytic group listed in Table 2.

Table 3. Workbook names for metropolitan areas and divisions
Metropolitan Statistical Areas (MSAs) and Divisions (1) Workbook name
(1) Unless otherwise noted, DAWN defines metropolitan areas using the Metropolitan Statistical Area (MSA) and Division definitions issued by the Office of Management and Budget (OMB) in June 2003 (available at http://www.whitehouse.gov/omb/bulletins/b03-04.html). For consistency, DAWN uses these names and definitions even if they were subsequently changed by OMB.
(2) Miami-Miami Beach-Kendall, FL, Division.
(3) Fort Lauderdale-Pompano Beach-Deerfield Beach, FL, and West Palm Beach-Boca Raton-Boynton Beach, FL, Divisions.
(4) Bronx, Kings, New York, Queens, and Richmond Counties, NY.
Boston-Cambridge-Quincy, MA-NH Boston_2011_{analytic group}.xls
Chicago-Naperville-Joliet, IL-IN-WI Chicago_2011_{analytic group}.xls
Denver-Aurora, CO Denver_2011_{analytic group}.xls
Detroit-Warren-Livonia, MI Detroit_2011_{analytic group}.xls
Miami-Dade County Division (2) Miami_Dade Div_2011_{analytic group}.xls
Miami-Fort Lauderdale Divisions (3) Miami_FortLauderdale Div_2011_{analytic group}.xls
Minneapolis-St. Paul-Bloomington, MN-WI Minneapolis_2011_{analytic group}.xls
New York-5 Boroughs Division (4) NewYork_5Boros Div_2011_{analytic group}.xls
Phoenix-Mesa-Scottsdale, AZ Phoenix_2011_{analytic group}.xls
San Francisco-San Francisco Division SanFrancisco_SF Div_2011_{analytic group}.xls
Seattle-Tacoma-Bellevue, WA Seattle_2011_{analytic group}.xls

1.4 Information organization and format

Workbooks and worksheets

With minor exceptions, each Excel workbook in the DAWN Trend Tables is organized the same way. Each workbook represents one geographic area and one analytic group. Each workbook contains 56 tables (worksheets), with each table representing visits for a single demographic or visit characteristic. Examples of a demographic characteristic are "male patients" or "patients aged 0 to 5." An example of a visit characteristic is "the patient was discharged home." Table 4 lists the tables that appear in each workbook. Unless otherwise noted in Table 4, each table in each workbook has the same arrangement of rows and columns.

Table 4. Tables in each workbook of the DAWN Trend Tables
Sheet tab label Description of visits included in table
Contents The Table of Contents lists each table that appears in the workbook. By clicking the table name, the user is taken automatically to that sheet in the workbook. A link to return to the Table of Contents is provided at the top and bottom of every spreadsheet.
Table Notes The table notes that appear in this spreadsheet apply to each table in the workbook. Also included here is the suggested citation to use when reproducing a table.
ED Visits by Drug All ED visits included in the analytic group (e.g., the workbook named "Nation_2011_Illicit.xls" includes just visits involving illicit drugs). See Table 1 for definitions of analytic groups. All tables in a workbook are limited to visits in the noted analytic group.
Male Visits involving male patients.
Female Visits involving female patients.
Gender UNK Visits for which gender of patient is not documented in ED visit records.
Under 21 Visits involving patients under the age of 21.
21 and older Visits involving patients aged 21 and older.
0 to 5 Visits involving patients aged 0 to 5.
6 to 11 Visits involving patients aged 6 to 11.
12 to 17 Visits involving patients aged 12 to 17.
18 to 20 Visits involving patients aged 18 to 20.
21 to 24 Visits involving patients aged 21 to 24.
25 to 29 Visits involving patients aged 25 to 29.
30 to 34 Visits involving patients aged 30 to 34.
35 to 44 Visits involving patients aged 35 to 44.
45 to 54 Visits involving patients aged 45 to 54.
55 to 64 Visits involving patients aged 55 to 64.
65 and older Visits involving patients aged 65 and older.
Age UNK Visits for which age of patient is not documented in ED visit records.
White Visits involving patients reported as White and not Hispanic or any other race/ethnicity.
Black Visits involving patients reported as Black and not Hispanic or any other race/ethnicity.
Hispanic Visits involving patients reported as Hispanic regardless of any other reported race/ethnicities.
Race_Ethnicity All Other Visits involving patients reported as one or more race/ethnicities other than White, Black, or Hispanic.
Race_Ethnicity UNK Visits for which race/ethnicity of patient is not documented in ED visit records.
No Evidence of Follow-up Visits involving patients for whom no evidence existed of follow-up care (e.g., treated and released to home or jail).
Evidence of Follow-up Visits involving patients for whom evidence existed of some type of follow-up care (e.g., referral to a detox program, admission to the hospital, transfer to another facility).
Disp_Treated and Released Combined category for visits involving patients treated and released to home, police/jail, or detox program.
Disp_Home Visits involving patients treated and released to home; subset of Disp_Treated and Released.
Disp_Police or Jail Visits involving patients treated and released to the police or sent to jail; subset of Disp_Treated and Released.
Disp_Referred to Detox Visits involving patients treated and released with a referral to a detox or treatment program; subset of Disp_Treated and Released.
Disp_Admitted Combined category for visits involving patients admitted to the hospital's intensive care unit (ICU), surgery, detox, or psychiatric or other inpatient unit ("other inpatient" includes "combo" units: e.g., psychiatric/detox unit).
Disp_ICU Visits involving patients admitted to the ICU; subset of Disp_Admitted.
Disp_Surgery Visits involving patients admitted for surgery; subset of Disp_Admitted.
Disp_Detox Visits involving patients admitted to the chemical dependency or detox unit in the hospital; subset of Disp_Admitted.
Disp_Psych Visits involving patients admitted to the psychiatric unit in the hospital; subset of Disp_Admitted.
Disp_Other Inpatient Visits involving patients admitted to another inpatient unit in the hospital; subset of Disp_Admitted.
Disp_All Other Disposition Combined category for visits involving patients who transferred, left without being seen, or died; other dispositions; and unknown dispositions.
Disp_Transferred Visits involving patients who transferred to another health care facility; subset of Disp_All Other Disposition.
Disp_Left Against Med Advice Visits involving patients who left against medical advice; subset of Disp_All Other Disposition.
Disp_Died Visits involving patients who died in the ED; subset of Disp_All Other Disposition.
Disp_Other Visits involving patients who had other dispositions; subset of Disp_All Other Disposition.
Disp_UNK Disposition of visit not documented in ED visit records; subset of Disp_All Other Disposition.
One Drug Visits involving only one drug.
Multi Drug Visits involving more than one drug.
Drugs with Alcohol Visits involving alcohol. For adults, the alcohol must have been used in combination with another drug to be reportable to DAWN. For patients under the age of 21, the alcohol may have been used either alone, with no other drug involvement, or with other drugs.
Two Drugs Visits involving exactly two drugs.
Three Drugs Visits involving exactly three drugs.
Four Drugs Visits involving exactly four drugs.
Five or More Drugs Visits involving five or more drugs.
Drug Combinations This table reports ED visits for major and mutually exclusive drug combination groups. That is, each visit is counted in one and only one drug combination group. The rows in this table do not conform to the standard template, but the columns do.
Drug Frequency This table reports counts of drugs, not ED visits. Each ED visit can involve up to 22 drugs. The estimates in this table reflect how often each drug was involved in ED visits. The rows and columns conform to the standard format.
Tox Confirmed Drugs This table reports counts of drugs, not ED visits. Each ED visit can involve up to 22 drugs. The estimates in this table reflect how often each drug involved was confirmed through toxicology testing. The rows and columns conform to the standard format.
Illicit Drugs This table reports ED visits for more detailed drugs and drug categories than are found in the standard format. The rows in this table do not conform to the standard template, but the columns do.
Psych Drugs Similar to expanded listing of illicit drugs but provides estimates for psychotherapeutic drugs.
Cen Nerv System Drugs Similar to expanded listing of illicit drugs but provides estimates for central nervous system drugs.
Respiratory Drugs Similar to expanded listing of illicit drugs but provides estimates for respiratory drugs.
Cardiovascular Drugs Similar to expanded listing of illicit drugs but provides estimates for cardiovascular drugs.

Rows

The rows of the tables represent drug categories and drugs. Each drug and each drug category appear on the same row in each table (e.g., the estimates of ED visits involving cocaine appear on row 15 in every table). The classification of drugs used in DAWN is derived from the Multum Lexicon, © 2012 Lexi-Comp, Inc., and/or Cerner Multum, Inc. The Lexicon was slightly modified to meet DAWN's need to report on illicit drugs using street names.

Columns

The 39 columns in each table provide the following information:

1.5 Special note on age categories

The age categories used for reporting ED visits in the DAWN Trend Tables reflect critical junctures in drug use. For example, patients aged 5 and under are reported separately to facilitate study of visits involving accidental ingestion. Patients aged 12 to 17 are considered to be in their formative years, and understanding the nature of their drug use is important for prevention efforts. Patients under the age of 21 are reported separately to facilitate study of topics such as underage drinking. Patients aged 18 to 20 are reported separately from those aged 21 to 24 to isolate drug-taking behaviors before and after the critical age of 21. Older patients are grouped in wider categories where age differences are not as critical to intervention and treatment. As a consequence, the age categories are not evenly sized—for example, the age group 30 to 34 covers 5 years, whereas the age group 35 to 44 covers 10 years. The size of an age group is an important consideration when comparing estimates of ED visits for different age categories. 

2. VALUES REPORTED IN DAWN TREND TABLES

The following values appear in the cells of the DAWN Trend Tables. The order in which values are listed here corresponds to the order in which they appear in the standard table format, going from left to right across the table. The section headings below match the overarching headings that appear in row 6 of the standard table format.

2.1 Weighted annual estimates

Estimates of drug-related ED visits are calculated by applying weights and adjustments to the data provided by the sampled hospitals participating in DAWN. The primary sampling weights reflect the probability of selection, whereas separate adjustment factors are included to account for nonresponse, data quality, and the known total of ED visits delivered by the universe of eligible hospitals, as reported by the most current American Hospital Association survey.  

Estimates of the number of visits are reported to the fifth decimal place, though they are formatted to appear as whole numbers. An asterisk (*) appears if a value is suppressed (see Section 2.6). All estimate fields are populated with a value or an asterisk; blanks do not appear and are not valid.

2.2 Rates per 100,000 population

All rates in the DAWN Trend Tables are visits per 100,000 persons. Rates are standardized measures that are helpful when comparing levels of drug-related ED visits for different years, types of visits, and demographic groups. DAWN rates for years and types of visits are based on the whole population; for example, there were 790.4 ED visits involving drug misuse or abuse per 100,000 population in 2011 compared with 552.9 visits in 2004. For specific age groups and sexes, the denominator is limited to the population in that age group or sex. For age in particular, rates are important because the size of the underlying population differs considerably across DAWN age groups (see Section 1.5). For example, in 2011 there were 13.5 million individuals aged 18 to 20 in the United States and 40.6 million aged 35 to 44. Accordingly, the estimated number of ED visits involving drug misuse or abuse was 239,281 visits for those aged 18 to 20 and 432,957 visits for those aged 35 to 44. To allow comparison between the two age groups, standardized rates are calculated as the number of ED visits per 100,000 persons in that age group. In this example, while the estimated number of visits was much lower for persons aged 18 to 20, the rate of visits was substantially higher: 1,771.5 for persons aged 18 to 20 compared with 1,065.7 visits for persons aged 35 to 44. Because they are reported as percentages, the RSEs provided in DAWN tables apply equally to the estimates and the rates.

Rates are reported to the ninth decimal place, though they are formatted to display only the first decimal (e.g., 123.4). Rates based on suppressed estimates are likewise suppressed, with an asterisk (*) appearing instead of a value (see Section 2.6). DAWN does not produce population-based rates for race/ethnicity categories because race/ethnicity information in ED records is often missing or is very limited. Three dots (…) appear in the rate fields in the race/ethnicity tables. All rate fields are populated with a value, asterisk, or three dots; blanks do not appear and are not valid.

2.3 Relative standard error (%)

Because DAWN relies on a sample of hospitals, each estimate produced from the DAWN ED data is subject to sampling variability, the variation in the estimate that would be observed naturally if different samples were drawn from the same population using the same procedures. The sampling variability of an estimate in this publication is measured by its relative standard error (RSE). The precision of an estimate or rate is inversely related to its RSE. That is, the greater the RSE, the lower the precision.

RSEs are reported to the ninth decimal place, though they are formatted to display only the first decimal (e.g., 12.3). The RSE values reported are percentages (e.g., 12.3 = 12.3%). Because it is reported as a percentage, an RSE measure applies to both the estimate and the rate. RSEs based on suppressed estimates are likewise suppressed, with an asterisk (*) appearing instead of a value (see Section 2.6). All RSE fields are populated with a value or an asterisk; blanks do not appear and are not valid.

2.4 Percent change (p < 0.05)

The DAWN Trend Tables assess between-year changes by comparing estimates as follows:

In the DAWN Trend Tables, 2011 Update, 2011 estimates are compared with those for 2004 (first year), 2009 (year before last), and 2010 (last year). The underlying formula is of the form: ((estimate for earlier year − estimate for later year) / estimate for earlier year). 

The resulting values are reported to the seventh decimal place, though they are formatted to display a whole number that represents a percentage difference (e.g., 12 = 12% increase in the number of visits). Declines in percentage difference appear as negative numbers (e.g., −12 = 12% decrease in the number of visits). The tables report percentage differences between years only if they are statistically significant at the p < 0.05 level; otherwise, a blank appears. A blank also appears if either estimate in the percentage difference formula is suppressed (see Section 2.6). Percent change measures for rates are not provided.

2.5 Lower and upper 95 percent confidence limit on weighted annual estimate

The DAWN Trend Tables include the lower and upper boundaries of the confidence intervals (CIs) for all estimates at the 95 percent confidence level. For example, the estimate of the number of ED visits involving any type of drug misuse or abuse in 2011 was 2,462,948 visits. A 95 percent CI means that if repeated samples were drawn from the same population of hospitals using the same sampling and data collection procedures, the number of ED visits reported (2,462,948 visits) will fall between the lower boundaries (2,112,868 visits) and upper boundaries (2,813,028 visits) 95 percent of the time.

The confidence limit estimates are reported to the eighth decimal place, though they are formatted to appear as whole numbers. An asterisk (*) appears if a value is suppressed (see Section 2.6). All CI fields are populated with a value or an asterisk; blanks do not appear and are not valid.

2.6 Suppression

DAWN estimates with RSE values greater than 50 percent or estimates based on fewer than 30 ED visits (weighted or unweighted) are considered too imprecise for publication and are not shown. An asterisk (*) is displayed in the place of a suppressed estimate or any value based on a suppressed estimate (i.e., rate, RSE, percent change, lower CI, upper CI).

End Notes

1 Links to the DAWN Trend Tables, 2011 Update, for the Nation and metropolitan areas as well as other DAWN materials are located at http://www.samhsa.gov/data/DAWN.aspx.
2 Major changes to DAWN were instituted in 2004 as the result of a redesign that altered most of DAWN's core features. Changes were made in the design of the hospital sample, the drug-related cases eligible for DAWN, the data items submitted on these cases, and the protocol for case finding and quality assurance. These improvements created a permanent disruption in trends. As a result, the base year for comparison to later years is 2004. 
3 Because of data limitations in 2004, the 2011 data for visits involving adverse reactions are compared with 2005, not 2004.


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