PTSD

Post-traumatic stress disorder symptoms following psychedelic use: a naturalistic survey study

This survey study (n=243) examined people who had distressing psychedelic experiences and found that about a third met self-reported DSM-5 criteria for PTSD afterwards. PTSD symptoms were linked to what happened during the acute experience, with avoidance associated with worse symptoms and acceptance linked to lower symptom severity and more post-traumatic growth.

Authors

  • Max Wolff

Published

Psychological Medicine
individual Study

Abstract

Background:

While clinical research on psychedelics often reports mild and transient side effects, broader survey studies indicate that a subset of users experiences lasting adverse mental health effects. This study investigated whether some of these meet diagnostic criteria for post-traumatic stress disorder (PTSD).

Methods:

A cross-sectional online survey (N = 243) was conducted with individuals reporting distressing psychedelic experiences with effects persisting beyond the acute phase (convenience sampling). It assessed characteristics of the acute experience, post-traumatic stress, post-traumatic growth, and coping strategies.

Results:

A total of 31.3% of participants met the DSM-5 criteria for PTSD as measured by self-report measures. PTSD symptom severity was strongly associated with characteristics of the acute experience. Avoidance-related experiences significantly predicted greater PTSD symptoms, while acceptance-related experiences were linked to lower symptom severity. Post-traumatic growth was unrelated to the intensity of the challenging experience or avoidance but positively predicted by acceptance-related experiences. Post-psychedelic help-seeking behavior was common: most consulted online resources or spoke with friends and family, though psychotherapy was rated the most helpful intervention.

Discussion:

Findings provide the first systematic evidence that difficult psychedelic experiences can be associated with later PTSD symptoms and highlight the critical role of acute psychological processes in shaping long-term outcomes. Since the survey targeted individuals with highly challenging acute experiences, the data do not allow the extrapolation of prevalence estimates to the broader population of psychedelic users. As psychedelic use expands beyond clinical settings, access to trauma-informed care and targeted integration support will be essential to minimize harm and support recovery.

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Research Summary of 'Post-traumatic stress disorder symptoms following psychedelic use: a naturalistic survey study'

Blossom's Take

In real-world settings, psychedelic experiences can lead to negative outcomes, and this study examined this population. Of those with "challenging or traumatic psychedelic experiences", a third would qualify for a PTSD diagnosis (this was self-diagnosed with the PCL-5 questionnaire). Whilst research usually focuses on the positive outcomes, this survey provides an in-depth analysis of what happens when things go wrong.

Introduction

Previous survey studies and qualitative reports have suggested that, although many psychedelic experiences are brief and manageable, a subset of users report persistent adverse psychological effects lasting months or years. However, those earlier studies mainly described broad symptom patterns rather than testing whether these longer-lasting difficulties could meet formal diagnostic criteria for post-traumatic stress disorder (PTSD). The paper also notes that challenging psychedelic states may involve intense fear, loss of control, resurfacing of traumatic memories, or distressing events occurring while intoxicated, any of which might plausibly contribute to post-traumatic stress symptoms. Evens and colleagues therefore aimed to examine whether enduring difficulties after a highly challenging psychedelic experience could meet DSM-5 PTSD criteria at the individual level, what participants considered the traumatic event to be, and how features of the acute experience related to later symptoms. They also explored post-traumatic growth and coping strategies, including which forms of help participants found useful. The study is presented as the first systematic investigation of PTSD-like outcomes following psychedelic use in a naturalistic sample.

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Study Details

  • Study Type
    individual
  • Journal
  • Topic
  • Author
  • APA Citation

    Evens, R., Uyar, A., Gosslau, E., Dambeck, F., Repantis, D., Wolff, M., & Lueken, U. (2026). Post-traumatic stress disorder symptoms following psychedelic use: a naturalistic survey study. Psychological Medicine, 56. https://doi.org/10.1017/s0033291726103754

References (23)

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