The New England journal of medicine
November 3, 2022
Guy M Goodwin, Scott T Aaronson, Oscar Alvarez et al.
1,095 citations
A single 25 mg dose of psilocybin, but not 10 mg, reduced depression scores more than a 1 mg control dose over three weeks in adults with treatment-resistant depression. In this phase 2 trial, 233 participants were randomly assigned to 25 mg, 10 mg, or 1 mg of synthetic psilocybin with psychological support. The 25 mg group showed an average 12-point drop on the MADRS depression scale versus a 5.4-point drop in the 1 mg group, a significant difference. The 10 mg group did not differ significantly from control. Response and remission rates at three weeks supported the primary result, but sustained response at 12 weeks was not significantly different.
Journal of affective disorders
January 15, 2025
Sara Ellis, Catherine Bostian, Wendy Feng et al.
23 citations
In a small, uncontrolled trial, 15 veterans with severe treatment-resistant depression received a single 25 mg dose of psilocybin. At three weeks, 60% met criteria for response and 53% for remission. By twelve weeks, 47% maintained response and 40% remission. Co-occurring PTSD did not affect outcomes, and the intensity of the psychedelic experience did not correlate with depression improvement. Four participants who needed to restart antidepressants were counted as non-responders from that point. No unexpected adverse events occurred. The authors note limitations including the small sample and lack of a control group, and call for further study.
Journal of affective disorders
June 9, 2025
Sara Ellis, Catherine Bostian, Anna Donnelly et al.
3 citations
Among veterans with severe treatment-resistant depression, a single 25 mg dose of psilocybin produced significant reductions in depression scores that were sustained for up to 12 months, though antidepressant effects began to wane after 6 months and more substantially after 9 months. At 12 months, 40% of 10 participants maintained a response (≥50% reduction in MADRS) and 30% maintained remission (MADRS ≤10). The study was a small, open-label pilot without a control group, so the findings suggest but do not demonstrate lasting benefit.