Therapeutic Potential of Psilocybin in Psychiatric Disorders: Mechanisms, Efficacy, and Clinical Implications

Psilocybin, a serotonergic psychedelic, has gained attention as a potential treatment for various psychiatric conditions. In this review, the authors summarize current clinical evidence related to psilocybin's efficacy, safety, and mechanisms of action across psychiatric disorders. Findings from early-phase and small-scale clinical trials suggest rapid but variable reductions in depressive symptoms, with some studies reporting sustained effects. Psilocybin has also shown preliminary benefits in alleviating anxiety related to life-threatening illness and in reducing substance use, including alcohol and tobacco dependence. Emerging but limited evidence supports possible therapeutic effects in the treatment of obsessive-compulsive disorder, body dysmorphic disorder, anorexia nervosa, and posttraumatic stress disorder. Reported adverse events, such as headache, nausea, and short-lived anxiety, are typically transient and mild; however, notable adverse reactions have occurred in larger randomized trials. Mechanistically, psilocybin may act by modulating limbic-prefrontal circuits, promoting synaptic plasticity, and enhancing emotional and cognitive flexibility, in particular when administered alongside structured psychotherapeutic support. Although the existing data are encouraging, the evidence base remains limited by small sample sizes, highly selective populations, and short follow-up durations. Larger, rigorously designed trials are required to confirm efficacy, establish long-term safety, and refine therapeutic protocols. Overall, psilocybin represents a promising but still experimental intervention that warrants further systematic investigation under controlled conditions.