Efficacy and Safety of Psilocybin-Assisted Therapy for Depression: A Meta-Analysis of Randomised Controlled Trials
Open Access Indonesian Journal of Medical Reviews April 21, 2026 Siti Nashria Rusdhy, Andrian Fajar Kusumadewi, Carla Raymondalexas Marchira et al.
Psilocybin-assisted therapy produces a large reduction in depressive symptoms, but the evidence is preliminary and limited by methodological problems. A meta-analysis of nine randomized controlled trials involving 514 participants found a large effect size (SMD = 1.270). However, the certainty of the evidence is rated low due to risk of bias, high heterogeneity, short-term follow-up, and publication bias. Effects were much larger when psilocybin was compared to a waitlist rather than an active placebo, and blinding is compromised by the drug's subjective effects. The authors conclude that robust Phase 3 trials are needed before routine clinical use.