Antidepressant effects of a single dose of ayahuasca in patients with recurrent depression: a preliminary report

TLDR

Ayahuasca, a natural psychedelic brew rich in DMT and harmine, is known to produce subjective well‑being and is hypothesized to have antidepressant effects. The study aimed to assess the antidepressant impact of a single ayahuasca dose in six patients experiencing a current depressive episode. An open‑label trial was conducted in an inpatient psychiatric unit to administer the dose and monitor outcomes. The single dose produced rapid, statistically significant reductions of up to 82 % in Hamilton, Montgomery‑Åsberg, and Brief Psychiatric Rating Scale depressive scores at 1, 7, and 21 days, with no significant changes in mania or thought‑content scales, indicating fast‑acting anxiolytic and antidepressant effects without inducing mania.

Abstract

Objectives: Ayahuasca (AYA), a natural psychedelic brew prepared from Amazonian plants and rich in dimethyltryptamine (DMT) and harmine, causes effects of subjective well-being and may therefore have antidepressant actions. This study sought to evaluate the effects of a single dose of AYA in six volunteers with a current depressive episode. Methods: Open-label trial conducted in an inpatient psychiatric unit. Results: Statistically significant reductions of up to 82% in depressive scores were observed between baseline and 1, 7, and 21 days after AYA administration, as measured on the Hamilton Rating Scale for Depression (HAM-D), the Montgomery-Åsberg Depression Rating Scale (MADRS), and the Anxious-Depression subscale of the Brief Psychiatric Rating Scale (BPRS). AYA administration resulted in nonsignificant changes in Young Mania Rating Scale (YMRS) scores and in the thinking disorder subscale of the BPRS, suggesting that AYA does not induce episodes of mania and/or hypomania in patients with mood disorders and that modifications in thought content, which could indicate psychedelic effects, are not essential for mood improvement. Conclusions: These results suggest that AYA has fast-acting anxiolytic and antidepressant effects in patients with a depressive disorder.