Lifetime use of psilocybin, tryptamine, and ketamine increased among U.S. adults from 2002 to 2019, while mescaline use declined. Among people aged 26 and older, use of most plant-based hallucinogens and dissociative agents rose, but adolescents and young adults showed decreases. Overall, use of these substances remains rare. The findings are based on nationally representative data from over one million respondents aged 12 and older.
Lifetime use of PCP is most strongly linked to hallucinogen dependence or abuse, increasing odds more than sixfold, while LSD, ketamine, and mescaline also raise odds of certain diagnostic criteria. Among 5,252 recent hallucinogen initiates, PCP use was associated with over six times higher odds of hallucinogen dependence or abuse (adjusted odds ratio 6.27), and it increased odds on all three main dependence and abuse criteria. LSD increased odds on two criteria, and ketamine and mescaline each increased odds on one criterion. MDMA, psilocybin, and peyote showed no significant associations. The findings suggest specific hallucinogens differ substantially in their links to disordered use.
Among U.S. residents aged 12 and older who reported substance use in 2021-2023, past-year ketamine use was more common among those receiving substance use disorder treatment (1.39%) than among those not in treatment (0.22%). Treatment was associated with higher odds of ketamine use across multiple substance types, including alcohol, marijuana, inhalant, methamphetamine, pain reliever, and opioid use disorders. The findings suggest that past-year treatment may be a marker of elevated ketamine exposure, highlighting the need for clinical screening and patient education about unsupervised ketamine risks.