Anxiety DisordersSchizophreniaSafety & Risk ManagementPsilocybin

Extended difficulties following the use of psychedelic drugs: A mixed methods study

This mixed‑methods study of 608 people reporting extended difficulties after psychedelic use found common problems—anxiety and fear, existential struggle, social disconnection and depersonalisation/derealisation—with about one third affected for over a year and one sixth for more than three years. Shorter duration was associated with knowing the dose and drug type and with lower acute difficulty, while a narrower range of difficulties was linked to taking the drug in a guided setting, with implications for harm reduction.

Authors

  • Ashleigh Murphy-Beiner
  • John Evans

Published

PLOS ONE
individual Study

Abstract

Long-term adverse experiences following psychedelic use can persist for weeks, months, or even years, and are relatively unexplored in psychedelic research. Our convergent mixed-method study gained quantitative and qualitative data from 608 participants who reported extended difficulties following psychedelic experiences. Data was gathered on the context of use, the nature and duration of the challenges they experienced (including a written description of these), plus a range of possible risk factors and perceived causes. The most common forms of extended difficulty were feelings of anxiety and fear, existential struggle, social disconnection, depersonalization and derealization. For approximately one-third of the participants, problems persisted for over a year, and for a sixth, they endured for more than three years. It was found that a shorter duration of difficulties was predicted by knowledge of dose, drug type and lower levels of difficulty reported during the psychoactive experience, while a narrower range of difficulties was predicted by taking the drug in a guided setting. Implications for psychedelic harm reduction are discussed.

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Research Summary of 'Extended difficulties following the use of psychedelic drugs: A mixed methods study'

Introduction

Evans and colleagues situate their study within the recent ‘‘psychedelic renaissance’’, noting renewed clinical and public interest in substances such as psilocybin, LSD, ayahuasca and MDMA. While much contemporary research focuses on therapeutic benefits and on challenging acute ‘‘trip’’ experiences, the authors identify a gap concerning adverse experiences that persist well beyond the pharmacological effects. Earlier studies and surveys suggest such extended difficulties can include anxiety, perceptual changes, derealisation/depersonalisation and, in some cases, psychotic symptoms or long-lasting distress, but prevalence estimates, phenomenology and predictors remain poorly characterised. This study aims to describe the types, phenomenology and perceived causes of difficulties that last more than 24 hours after a psychedelic experience, and to test hypotheses about predictors of the range and duration of those difficulties. Using a convergent mixed-methods approach, the investigators collected quantitative checklist data and brief written narratives from people who reported enduring problems, with the goal of combining epidemiological description and inductive qualitative analysis to inform harm-reduction and future research priorities.

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Study Details

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