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.
A team at Geneva University Hospitals developed an interdisciplinary model for psychedelic-assisted psychotherapy (PAP) that combines the altered state of consciousness induced by LSD or psilocybin with traditional dialogue-based psychotherapy. Since 2014, Swiss law has allowed exceptional medical authorizations for these substances. From September 2020 to February 2024, the team received 224 personal authorizations (114 for LSD, 110 for psilocybin) and conducted 396 individual sessions. The protocol includes patient selection, preparatory psychoeducation, controlled substance administration, and integration sessions. The authors argue that psychedelic-induced consciousness alteration can act as a catalyst to revive stalled psychotherapeutic processes and call for continued research and broader clinical integration of PAP.