Psychiatry research
November 1, 2023
Sipan Haikazian, David C J Chen-Li, Danica E Johnson et al.
121 citations
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.
Journal of affective disorders
April 15, 2026
Gia Han Le, Sabrina Wong, Danica E Johnson et al.
4 citations
Ketamine and esketamine rapidly reduce depression in people with treatment-resistant depression and bipolar depression, but the synaptic mechanisms behind dosing and durability are unclear. This review of 61 clinical and 17 preclinical studies found that a single 0.5 mg/kg intravenous infusion produces antidepressant effects peaking at 24 hours and fading over 2-3 days. Early neurophysiological changes appear within 3-8 hours, consolidate by 24 hours, and are rarely detected beyond 3 days. Twice-weekly and thrice-weekly dosing produce comparable four-week outcomes, and weekly maintenance reduces relapse risk. Ketamine may open a plasticity window lasting about 2-3 days, and aligning dosing intervals with this window could optimize durability while minimizing drug exposure.
Psychiatry research
July 1, 2026
Erin Artna, Guneet Sandhu, Noah Chisamore et al.
1 citation
Borderline personality disorder (BPD) is a serious mental illness with limited treatment options. Although patients with BPD are often excluded from psychedelic research due to safety concerns about suicide and substance misuse, emerging evidence suggests psychedelics may target core BPD symptoms and common co-occurring mood and anxiety disorders. This narrative review analyzed 22 studies from multiple databases examining ketamine, esketamine, and psilocybin in individuals with BPD. Preliminary evidence indicates these psychedelics may be safe and effective for improving core BPD symptoms and socio-occupational functioning, but more high-quality research focused on BPD-specific outcomes is needed to clarify their potential as a treatment modality.
The Canadian Journal of Psychiatry
March 25, 2025
Noah Chisamore, Erica S Kaczmarek, Zoe Doyle et al.
1 citation
A single 25 mg dose of psilocybin combined with psychotherapy produced clinically significant reductions in depression, anxiety, and suicidality symptoms over two months in people with treatment-resistant depression. Among 27 participants, those who tapered off antidepressant medications before treatment (n = 18) and those not on antidepressants at screening (n = 9) showed comparable improvements, with no significant differences between groups on clinician-rated depression, self-reported depression, anxiety, or suicidality. The intensity of the psychedelic experience was also similar. These results suggest that tapering antidepressants before psilocybin-assisted psychotherapy may not diminish therapeutic benefits, though further research is needed.
European neuropsychopharmacology : the journal of the European College of Neuropsychopharmacology
February 1, 2025
Danica E Johnson, Nelson B Rodrigues, Sydney Weisz et al.
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.