A single 25 mg dose of psilocybin, given with psychological support, was safe and well-tolerated in 22 adults with PTSD. No serious adverse events occurred, and most side effects (headache, nausea, crying, fatigue) resolved within a day. PTSD symptoms, measured by the CAPS-5 scale, showed a clinically meaningful average decrease of nearly 30 points at 4 and 12 weeks after the dose, and this improvement was linked to the intensity of the psychedelic experience. Functional impairment and quality of life also improved. The open-label design and small sample size mean further controlled trials are needed to confirm efficacy.
In a 12-week clinical trial of 25 mg COMP360 psilocybin for 22 participants with post-traumatic stress disorder, audio recordings showed that during drug-administration sessions speech by either party was rare: silence filled 78% of the time on average, compared to 25% to 30% in non-administration sessions. Thematic analysis of post-dosing interviews revealed that support was minimally enacted but experientially salient, autonomy was promoted through the introspective state and non-directive support, and primary modes of support during altered states included reassurance and validation. The minimal verbal interaction distinguishes this monitoring and support from conventional psychotherapies and MDMA-assisted therapy.