There were an estimated 122,000 new heroin users in 1994. Estimates of heroin incidence are subject to wide variability and do not show any clear trend, although the 1994 estimate of new users is larger than estimates for prior recent years, a finding that is consistent with anecdotal reports of increasing numbers of new heroin users.
There were an estimated 912,000 new hallucinogen users in 1994. The rate among youths age 12-17 increased between 1991 and 1994, from 11.2 to 23.3 per 1,000 person years.
There were an estimated 666,000 new inhalant users in 1994, up from 428,000 in 1991. The rate of first use among youths age 12-17 rose significantly from 1991 to 1994, from 11.2 to 22.2 per 1000 person years in 1994.