Psilocybin treatment for symptoms of depression: a living systematic review, meta-analysis, and data resource
medRxiv August 16, 2025 S. Parker Singleton, Brooke L. Sevchik, Analiese Lahey et al. preprint
Psilocybin-assisted therapy produces substantial reductions in depressive symptoms compared to control conditions, according to a systematic review and meta-analysis of 12 randomized controlled trials with 711 participants. The pooled effect size was large (Hedges' g = –0.91), and effects appeared rapidly and remained consistent over several weeks. However, many studies had small sample sizes or risk of bias, and waitlist-controlled or crossover designs contributed heterogeneity. The review provides a living open data resource that will be updated as new evidence emerges.