PTSDVeteransSafety & Risk ManagementPersonality & Trait FactorsAyahuasca

Prevalence and therapeutic impact of adverse life event reexperiencing under ceremonial ayahuasca

Among 339 ayahuasca retreat participants, reexperiencing of adverse life events during ceremonies was common—particularly sexual assault among women, combat trauma among veterans and in those with lifetime PTSD—and was linked to cognitive reappraisal, psychological flexibility and acute discomfort. Those who reexperienced adverse events showed larger reductions in trait neuroticism at follow-up, suggesting such reexperiencing may contribute to the therapeutic effects of ceremonial ayahuasca.

Authors

  • David Erritzoe
  • Brandon Weiss

Published

Scientific Reports
individual Study

Abstract

The present study examined the safety and efficacy of the ceremonial use of ayahuasca in relation to reports of heightened life event reexperiencing under psychedelics. The study examined (1) the prevalence of specific types of adverse life event reexperiencing, (2) characteristics predictive of reexperiencing, (3) the psychological character of reexperiencing, and (4) the impact of reexperiencing on mental health. Participants were recruited from three ayahuasca healing and spiritual centers in South and Central America (N = 33 military veterans, 306 non-veterans) using self-report data at three timepoints (Pre-retreat, Post-retreat, 3-months post-retreat). Reexperiencing adverse life events under ayahuasca was common, with women showing particularly high probability of reexperiencing sexual assault, veterans reexperiencing combat-related trauma, and individuals with a self-reported lifetime diagnosis of post-traumatic stress disorder exhibiting a substantively higher prevalence of reexperiencing. Reexperiencing was associated with states of cognitive reappraisal, psychological flexibility, and discomfort during ceremonies, and participants who reexperienced adverse life events exhibited greater reductions in trait neuroticism following their ceremonies. Clinical implications of these results for the application of psychedelics to mood and stress disorders are discussed.

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Research Summary of 'Prevalence and therapeutic impact of adverse life event reexperiencing under ceremonial ayahuasca'

Introduction

As psychedelic therapies gain acceptance as tools for mental health care, important questions about safety and efficacy in relation to individual vulnerability factors remain incompletely addressed. One such factor is the potential for psychedelic experiences — particularly at moderate to high doses — to surface autobiographical memories of adverse life events, including trauma. Understanding whether such reexperiencing occurs, who is most susceptible, and what its psychological consequences are has direct relevance to screening, preparation, and support protocols in both ceremonial and clinical settings. This study examined the prevalence of adverse life event reexperiencing during ayahuasca ceremonies, identified demographic and clinical characteristics predictive of reexperiencing, and evaluated whether reexperiencing confers therapeutic benefit or poses psychological harm, using a prospective design in a naturalistic retreat sample.

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