Decreases in State and Trait Anxiety Post-psilocybin: A Naturalistic, Observational Study Among Retreat Attendees
In a naturalistic observational study of retreat attendees, ingestion of psilocybin-containing truffles in a supportive group setting produced rapid and sustained reductions in both state and trait anxiety up to one week post-ceremony. Reductions were predicted by the intensity of ego dissolution and accompanied by decreased neuroticism and increased mindful non-judging, supporting the feasibility and potential anxiolytic efficacy of group psychedelic sessions.
Authors
- Kim Kuypers
- Johannes Ramaekers
- Nathalie Mason
Published
Abstract
Anxiety disorders are the most common type of psychiatric disorders among Western countries. Evidence-based treatment modalities including pharmacological and cognitive-behavioral therapy result in deficient treatment responses. Historical and recent research suggests psychedelic drugs may be efficacious in alleviating anxiety-related symptoms among healthy and clinical populations. The main aim of the present study was investigation of the effects of psilocybin-containing truffles, when taken in a supportive group setting, on ratings of state and trait anxiety across self-reported healthy volunteers. Attendees of psilocybin ceremonies were asked to complete a test battery at three separate occasions: before the ceremony (baseline), the morning after, and 1 week after the ceremony. The test battery included questionnaires assessing state and trait anxiety (State-Trait Anxiety Inventory), mindfulness capacities (Five Facet Mindfulness Questionnaire), and personality (Big Five Inventory). Additionally, the psychedelic experience was quantified with the Persisting Effects Questionnaire and the Ego Dissolution Inventory. The total amount of psilocybin-containing truffles consumed by each participant was recorded, and a sample of the truffles was analyzed to determine psilocin concentrations. Fifty-two attendees (males = 25; females = 25; others = 2) completed parts of the baseline assessment, 46 (males = 21; females = 24; others = 1) completed assessments the morning after the ceremony, and 23 (males = 10; females = 13) completed assessments at the 1-week follow-up. Average psilocin consumption across individuals was 27.1 mg. The morning after the ceremony, we observed medium reductions in anxiety measures (both state and trait) compared to baseline ( d ¯ = 6.4; p < 0.001 and d ¯ = 6; p = 0.014, respectively), which persisted over a 1-week period post-ceremony ( d ¯ = 6.7; p = 0.001 and d ¯ = 8.6; p = 0.004, respectively). At 1 week post-ceremony, the non-judging facet of the mindfulness scale was increased ( d ¯ = 1.5; p = 0.03), while the personality trait neuroticism decreased ( d ¯ = 5.2; p = 0.005), when compared to baseline. Additionally, we found ratings of ego dissolution (mean: 59.7, SD: 28.3) and changes in neuroticism to be the strongest predictors of reductions in state and trait anxiety, respectively. In sum, results suggest rapid and persisting (up to 1 week) anxiolytic effects in individuals with sub-clinical anxiety symptoms, which are related to the acute experience of ego dissolution, as well as lasting changes in trait neuroticism. Results also add support to the feasibility and potential efficacy of group sessions with psychedelics. To understand whether these effects extend to wider populations suffering from heightened anxiety, and the mechanisms involved, further experimental research is needed.
Research Summary of 'Decreases in State and Trait Anxiety Post-psilocybin: A Naturalistic, Observational Study Among Retreat Attendees'
Introduction
Anxiety disorders are highly prevalent and burdensome worldwide, yet existing treatments yield only partial response rates (typically around 50–58% for pharmacological or cognitive-behavioural approaches). Historical and contemporary research has suggested that psychedelic substances—including psilocybin—can reduce anxiety symptoms in clinical and naturalistic samples, sometimes producing durable effects after a single administration. Two psychological candidates for mediating such effects are reductions in the personality trait neuroticism and enhancements in mindfulness capacities; additionally, the intensity or quality of the acute psychedelic experience (for example, ego dissolution) has been linked to longer‑term outcomes in prior work. Kiraga and colleagues designed a naturalistic observational study to examine whether ingestion of psilocybin-containing truffles in a supportive retreat context produces sub-acute and one‑week reductions in state and trait anxiety among volunteer attendees. The investigators also set out to test whether post‑retreat changes in mindfulness and neuroticism occur, and whether these psychological changes—or acute ratings of ego dissolution—predict reductions in state and trait anxiety. The study therefore aimed to characterise short-term anxiolytic effects and potential psychological mechanisms in a real‑world group setting.
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Kiraga, M. K., Kuypers, K. P. C., Uthaug, M. V., Ramaekers, J. G., & Mason, N. L. (2022). Decreases in State and Trait Anxiety Post-psilocybin: A Naturalistic, Observational Study Among Retreat Attendees. Frontiers in Psychiatry, 13. https://doi.org/10.3389/fpsyt.2022.883869
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