Longterm effects of ayahuasca in patients with recurrent depression: a 5-year qualitative follow-up

This qualitative follow-up study (n=8) interviewed patients 4-7 years after the intake of ayahuasca (123.2 mg DMT, 32.34mg Harmine) within the context of a previous open-label study; most patients reported that the experience was among the most important of their lives.

Abstract

Introduction: Ayahuasca is a botanical hallucinogenic preparation traditionally used by indigenous populations of Northwestern Amazonian countries for ritual and therapeutic purposes. It is rich in β-carboline alkaloids and N,N-dimethyltryptamine (DMT). Preclinical, observational, and experimental studies suggest that ayahuasca and its alkaloids have anxiolytic and antidepressive effects. We recently reported in an open-label trial that ayahuasca administration was associated with significant decreases in depression symptoms for 2-3 weeks after the experimental session in 17 patients with treatment-resistant major depressive disorder.

Objectives: To investigate if the experiment had any long-lasting effects on patients.

Methods: Eight patients were interviewed 4 to 7 years after ayahuasca intake.

Results: Our results suggest that ayahuasca was well tolerated and that symptom reductions were limited to a few weeks. Importantly, most patients believed that the experience was among the most important of their lives, even 4-7 years later.

Discussion: To the best of our knowledge, this is the first long-term follow-up of a clinical sample that participated in an ayahuasca trial. Further studies with different and repeated dosing should be designed to further explore the antidepressive and anxiolytic effects of ayahuasca.

Authors: Rafael G. dos Santos, Rafael Faria Sanches, Flávia de Lima Osório, Jaime E. C. Hallak

Summary

Received: 10/21/2017 – Accepted: 2/6/2018

Ayahuasca, a botanical hallucinogenic preparation, was well tolerated and was associated with significant decreases in depression symptoms in 17 patients with treatment-resistant major depressive disorder. However, the effects were limited to a few weeks and patients believed that the experience was among the most important of their lives.

Introduction

Ayahuasca is a botanical hallucinogenic preparation traditionally used by indigenous populations of Northwestern Amazonian countries for ritual and therapeutic purposes. It is also used as a sacrament and therapeutic tool by Brazilian syncretic religions.

Studies with healthy volunteers and psychiatric patients show that ayahuasca may have anxiolytic, antidepressive, and antiaddictive effects. Observational studies among Santo Daime members have shown significant reductions on panic-like and depressive symptoms.

We recently reported that administration of ayahuasca to patients with treatment-resistant major depressive disorder decreased depression symptoms from 80 minutes to day 21. We recently replicated these results in a parallel arm, double-blind, randomised, placebo-controlled trial with 35 patients with treatment-resistant MDD.

We interviewed the volunteers after a long-time period to ask if the experiment had any long-lasting effects on them.

Methods

Three attempts were made to contact the volunteers by telephone, and they were asked to classify their experience with ayahuasca as negative, neutral/stable, or positive.

Results

Eight out of 17 patients could be contacted, and their mean HAM-D and MADRS scores were 20.37 (range 17-24) and 27.12 (range 21-32) respectively. They were interviewed after a mean of 56.37 months (range 49-76), or 4.7 years.

Although some volunteers had difficult experiences, most reported that participation on the study was positive and had a positive impact on their general and daily lives. However, many reported that their symptoms remained stable or were unchanged, and most reported short-lived positive effects.

Discussion

Previous studies in members of the Brazilian ayahuasca churches reported that ayahuasca may have anxiolytic and antidepressive effects. In the present work, the first long-term follow-up of those depressed volunteers was conducted, and ayahuasca was well tolerated and associated with antidepressive effects.

Even considering the above-cited limitations, the results suggest that ayahuasca was well tolerated by these patients and that the reductions in depressive symptoms attributed to ayahuasca intake were limited to a few weeks.

The results of this qualitative study suggest that future studies involving administration of ayahuasca should try to perform follow-ups after shorter periods of time and should avoid losing contact with the volunteers.

Declaration of conflicting interests and source of funding

This research was conducted at the Department of Neurosciences and Behavior, Ribeiro Preto Medical School, University of So Paulo, Ribeiro Preto, Brazil. It was funded by Fapesp and ICEERS.