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.
Social functioning problems are common in mental health disorders, but effective treatments are limited. Analyzing data from a large U.S. national survey (2015–2019, over 214,000 adults), lifetime use of MDMA/ecstasy was linked to lower odds of three social difficulties: dealing with strangers (9% lower odds), participating in social activities (10% lower odds), and being prevented from social activities (16% lower odds). Lifetime mescaline use was also linked to lower odds of difficulty with strangers (15% lower odds). Other psychedelics showed no benefit or were associated with increased social difficulties. The authors note that experimental studies are needed to determine if these relationships are causal.