A systematic review and meta-analysis assessed the risk of psychedelic-induced psychosis in people with schizophrenia. Among population studies, the incidence was 0.002%; in uncontrolled trials, 0.2%; and in randomized controlled trials, 0.6%. In uncontrolled trials that included individuals with schizophrenia, 3.8% developed long-lasting psychotic symptoms. Of those who experienced psychedelic-induced psychosis, 13.1% later developed schizophrenia. The evidence suggests schizophrenia might not be an absolute exclusion for clinical trials on psychedelics for treatment-resistant depression and negative symptoms, but low study quality and limited data warrant a conservative approach until more research is done.
Psychedelic-induced psychosis is rare, occurring in less than 1% of users in controlled trials, but evidence on its treatment is limited. A systematic review of 93 cases from 1955 to 2024 found that LSD (47.3%) and MDMA (38.7%) were the most common substances involved, with an average patient age of 23.7 years and 88% male. Psychosis lasted about 1.8 weeks on average. Second-generation antipsychotics had a response rate of 91.3%, significantly higher than first-generation antipsychotics at 27%. Electroconvulsive therapy also showed a 91% response rate. Follow-up revealed 34% of patients later developed schizophrenia spectrum disorders and 20.4% bipolar disorder, though limited follow-up data constrain these findings.