Real-world effectiveness and safety of psychedelic-assisted psychotherapy: Outcomes from a large-scale compassionate use cohort in Switzerland
This study aimed to determine whether psychedelic-assisted psychotherapy is effective and safe in real-world clinical practice, and whether outcomes differ between LSD and psilocybin while also examining changes in emotional regulation.
Highlights of the study
Psychedelic treatment data from 115 compassionate use patients were reported.
Psychedelic-assisted psychotherapy significantly reduced depression and anxiety.
LSD and psilocybin showed comparable clinical outcomes and safety profiles.
Treatment was well-tolerated and improved cognitive emotion regulation.
Background
Classic serotonergic psychedelics such as LSD and psilocybin show promising antidepressant effects in controlled trials, but real-world data from routine clinical care remain limited.
Methods
This study retrospectively analysed routine data from adults with treatment-resistant depressive and/or anxiety disorders who received a first standardized Psychedelic-assisted Psychotherapy (PAP) cycle with 100 µg LSD or 25 mg psilocybin at a Swiss university hospital (May 2024–October 2025). Self-reported depression (BDI) and trait anxiety (STAI-T) were assessed at screening, one month before treatment, and 1–3 months post-treatment. In a subset of participants, cognitive emotion regulation (CERQ) was assessed pre- and post-treatment. Subjective drug effects and adverse events were recorded on the treatment day.
Results
The sample consisted of 115 patients (56.5 % female; Mean age = 47.5 years). Depressive and anxiety symptoms significantly decreased over time (BDI: F(2178) = 63.50, p < 0.001, partial η² = 0.42; STAI-T: F(1.74,145.9) = 16.97, p < 0.001, partial η² = 0.17), with no main effect of substance. CERQ analyses indicated reduced self-blame, rumination and catastrophizing, and increased positive refocusing and reappraisal. Perceived intensity followed distinct temporal profiles for LSD and psilocybin, but comparable subjective drug effects and clinical outcomes. Adverse events were mostly mild and transient, with no serious complications or treatment discontinuations.
Conclusions
In this compassionate-use real-world cohort, a first fully-active dose PAP session with LSD or psilocybin was well tolerated and associated with significant improvements in depressive and anxiety symptoms. These findings support the feasibility and effectiveness of PAP in specialised routine care.
Aboulafia-Brakha T, Buchard A, Mabilais C, Alaux S, Amberger C, Furtado L, Seragnoli F, Briefer JF, Thorens G, Sabé M, Szczesniak L, Iuga R, Zullino D, Penzenstadler L. Real-world effectiveness and safety of psychedelic-assisted psychotherapy: Outcomes from a large-scale compassionate use cohort in Switzerland. Psychiatry Res. 2026 Apr;358:116992. doi: 10.1016/j.psychres.2026.116992. Epub 2026 Feb 2. PMID: 41643299. Read Paper
For more psychedelic news and research, visit the psychedelic health professional network homepage.
