A review of clinical trials on psychedelic drugs for psychiatric disorders found the strongest evidence for MDMA and psilocybin, both designated by the FDA as breakthrough therapies for PTSD and treatment-resistant depression, respectively. Evidence for LSD and ayahuasca is observational but suggests potential therapeutic effects for mood, anxiety, trauma, and substance use disorders, as well as end-of-life care. Of 1,603 articles screened, 14 well-designed trials were identified. The database remains insufficient for FDA approval of any psychedelic for routine clinical use, but continued research is warranted.
Current evidence does not support recommending psilocybin combined with psychological support (PST) as a psychiatric treatment. More rigorous clinical trials are needed to confirm its effectiveness in larger and more diverse patient groups, determine appropriate dosing, improve blinding methods, and understand how it works and for whom it works best. Comparing it directly with other proven treatments will clarify its potential future role in treating major psychiatric disorders.