Online Masterclass

Therapeutische toepassingen

van psychedelica in de GGZ

Cory Weissman, MD

University of Toronto

Rapid and Sustained Remission of Suicidality with a Single Dose of Ayahuasca in Recurrent Major Depressive Disorder



Suicidality is a growing epidemic and current treatment options are limited. One previous, positive study explored the effects of ayahuasca on suicidality in major depressive disorder (MDD), although this study had significant limitations with only 7 days of follow-up and high levels of psychiatric comorbidity (1). Further research into the efficacy of ayahuasca to treat suicidality is warranted.


We conducted a secondary analysis of an open-label trial in which individuals with recurrent MDD received a single dose of ayahuasca (n=17). The primary outcomes were remission from suicidality as indexed by the suicide items on the Hamilton Rating Scale for Depression (HRSD) and the Montgomery-Asberg Depression Rating Scale (MADRS). Suicidality was assessed at baseline, during the acute effects of the ayahuasca and 1, 7, 14, and 21 days after the intervention.


Of patients with baseline suicidality present, as indexed by the HRSD suicide item (n=12), 83% achieved full and sustained remission of their suicidality. The result was very similar on the MADRS suicide item (80% remission for n=15). Effect sizes at day 21 of follow-up were large and significant, according to paired t-tests (Cohen’s d=2.4, p<0.001 for HRSD suicide item; d=1.9, p<0.001 for MADRS suicide item).


These results provide support for the role of ayahuasca as an intervention for suicidality in patients with recurrent MDD. Limitations of this study include the open-label design and small sample size. Future studies should investigate ayahuasca in a randomized-controlled trial with a larger sample size in patients with MDD.


Hi there, my name is Cory Weissman and I am a senior psychiatry resident and a member of the clinician-scientist program at the University of Toronto, in Canada. My current research focus is in interventional treatments for suicidality, specifically brain stimulation and psychedelic modalities. I will be completing my residency training next year and am in the midst of a MSc in pharmacology. I personally believe that current discoveries in the clinical neurosciences hold great promise for the future of psychiatry. This is why I am devoting my career to investigating how emerging brain-based interventional treatments work on a translational level.



Learn about new events and breakthroughs in the psychedelic scientific community.