Psilocybin for major depressive disorder: An updated systematic review and meta-analysis of randomized clinical trials
Sepehr Aghajanian, Arman Shafiee, Samira Parvizi Omran, Aida Rezaei Nejad, Kyana Jafarabady, Omid Kohandel Gargari, Shahryar Rajai, Ida Mohammadi, Touran Bahrami Babaheidari, Mahmood Bakhtiyari
Journal of Psychopharmacology October 31, 2024 DOI: 10.1177/02698811241287542 via OpenAlex
Summary
AI-generated from the abstractPsilocybin, a classic hallucinogen, produces a large and clinically observable reduction in depressive symptoms when added to supportive therapy, compared to baseline measurements and to placebo. The effect remains significant across various time intervals after administration. This systematic review and meta-analysis substantiates that psilocybin is superior to psychotherapy alone for treating depression, warranting further studies with larger samples and longer follow-up.
Study at a glance
| Characteristics | Systematic review and meta-analysis Randomized Peer reviewed |
|---|---|
| Intervention | Psilocybin |
| Topics | Depression Psilocybin |
| Keywords | Psychedelics hallucinogens Entheogens Psychoactive drugs Psychological wellbeing Behavioral health |
| Citations | 12 |
| Key finding | Psilocybin plus supportive therapy yields a large reduction in depressive symptoms compared to baseline and placebo, and the effect persists over time. |
Abstract
Background: Due to the unsatisfactory therapeutic effects of current antidepressants, research has been launched into alternative treatment approaches, such as the administration of psychedelics. Psilocybin, a classic hallucinogen, has been shown to exert considerable positive influence on depression symptoms through its serotonergic and glutamatergic effects. This systematic review and meta-analysis aimed to evaluate the effectiveness of psilocybin in treating depression. Methods: A comprehensive search of Medline (via PubMed) and the Cochrane Library databases was conducted to identify relevant studies. Inclusion criteria were applied to select studies that investigated the therapeutic impact of psilocybin on depression. A mixed-effects multi-level model was used to estimate the overall effect size. Effectiveness over time was also investigated as a secondary analysis. Results: The results of the primary analysis revealed a large and clinically observable reduction (SMC: −1.24, 95%CI: −1.83 to −0.65, I 2 level2 = 11.39%, I 2 level3 = 77.67%) of depressive symptomatology in patients receiving psilocybin in addition to supportive therapy compared to baseline measurements. The decrease was also marked when compared to placebo ( p-value = 0.032). The results remained significant even when a secondary analysis assessed the effect in various time intervals since the administration of psilocybin. Conclusion: This systematic review and meta-analysis substantiate the claim that psilocybin is superior in treating depression compared to established psychotherapy alone used for treating depression. This finding warrants further studies with larger sample sizes and across a longer timeframe.