A placebo-controlled study of the effects of ayahuasca, set and setting on mental health of participants in ayahuasca group retreats
Psychopharmacology – March 10, 2021
Source: OpenAlex
Summary
Strikingly, participants experiencing Ayahuasca ceremonies reported improved mental health, including reduced anxiety and depression, even when receiving a Placebo. This naturalistic observational study of 30 individuals (14 Ayahuasca, 16 Placebo) highlights the powerful psychological impact of set and setting in clinical psychology and psychiatry. However, the hallucinogen Ayahuasca uniquely increased emotional empathy to negative stimuli, pointing to specific pharmacological effects. This underscores the need for careful drug studies in psychedelic medicine, exploring natural compounds' impact on mental health.
Abstract
Abstract Ayahuasca is a plant concoction containing N,N -dimethyltryptamine (DMT) and certain β-carboline alkaloids from South America. Previous research in naturalistic settings has suggested that ingestion of ayahuasca can improve mental health and well-being; however, these studies were not placebo controlled and did not control for the possibility of expectation bias. This naturalistic observational study was designed to assess whether mental health changes were produced by ayahuasca or by set and setting. Assessments were made pre- and post-ayahuasca sessions in 30 experienced participants of ayahuasca retreats hosted in the Netherlands, Spain, and Germany. Participants consumed ayahuasca ( N = 14) or placebo ( N = 16). Analysis revealed a main effect of time on symptoms of depression, anxiety, and stress. Compared to baseline, symptoms reduced in both groups after the ceremony, independent of treatment. There was a main treatment × time interaction on implicit emotional empathy, indicating that ayahuasca increased emotional empathy to negative stimuli. The current findings suggest that improvements in mental health of participants of ayahuasca ceremonies can be driven by non-pharmacological factors that constitute a placebo response but also by pharmacological factors that are related to the use of ayahuasca. These findings stress the importance of placebo-controlled designs in psychedelic research and the need to further explore the contribution of non-pharmacological factors to the psychedelic experience.