Mapping Psilocybin-Assisted Therapies: A Scoping Review

We conducted a scoping review on psilocybin-assisted therapy for addiction, depression, anxiety and post-traumatic stress disorder. Psilocybin is a naturally-occurring tryptophan derivative found in species of mushroom with psycho-active properties. From 2022 records identified by database searching, 40 publications were included in the qualitative synthesis from which we identified 9 clinical trials with a total of 169 participants. Trials used a peak-psychedelic model of therapy, emphasizing inward journey through the use of eyeshades, set musical scores and with medium to high doses of psilocybin. No serious adverse effects were reported; mild adverse effects included transient anxiety, nausea and post-treatment headaches. Overall, the 9 trials all demonstrated safety, tolerability and preliminary efficacy in the treatments of obsessive-compulsive disorder, substance use disorder, treatment-resistant unipolar depression, anxiety or depression in patients with life-threatening cancer and demoralization among long-term AIDS survivors.The literature was found to be early and exploratory, with several limitations: only 5 were randomized controlled trials, small and homogenous patient sample size, difficulties in blinding, and the confounding influence of psychological supports provided. Further research is indicated to establish effectiveness for these and other indications, with a more diverse range of patients, and with differing program and dosing modalities. Keywords: psilocybin, psychedelic, psychedelic-assisted therapy, scoping review, depression, anxiety, obsessive-compulsive disorder, end-of-life distress, substance use disorder