Mood Disorders Psychopharmacology Unit, Poul Hansen Depression Centre, University Health Network, Toronto, ON, Canada; Institute of Medical Science, University of Toronto, Toronto, ON, Canada.
3 papers in the library · 127 citations · publishing 2023-2025
A systematic review and meta-analysis of 13 studies (686 participants) found that psilocybin therapy produced a large reduction in depressive symptoms compared to control conditions, with a standardized mean difference of -0.78. Response and remission rates were also significantly higher with psilocybin. Open-label trials showed robust decreases in depression after psilocybin administration. The findings suggest antidepressant efficacy for psilocybin-assisted psychotherapy, but the authors note that further studies are needed to confirm safety and efficacy and to optimize treatment protocols.
In a real-world clinic setting, a single ketamine infusion significantly reduced suicidal ideation among 96 adults with treatment-resistant depression, as measured by the Columbia Suicide Severity Rating Scale. The reduction shifted the group average from active toward passive suicidal thoughts. A mediation analysis showed that ketamine's antisuicidal effects are partially independent of its antidepressant effects, suggesting a direct benefit on suicidality beyond mood improvement. The findings support ketamine's effectiveness for suicidal ideation outside controlled clinical trials.
Depression with co-occurring posttraumatic stress disorder (PTSD) leads to more severe symptoms and poorer response to standard treatments. In a retrospective analysis of 134 patients with treatment-resistant depression, four ketamine infusions (0.5-0.75 mg/kg) reduced depressive symptoms equally in those with and without comorbid PTSD; no significant group-by-time interaction was found. PTSD symptoms also significantly improved across all symptom clusters, with moderate to large effect sizes. Ketamine shows promise as an effective intervention for this hard-to-treat population, though future randomized trials should explore factors driving improvement and long-term outcomes.