Stress Experience Following Psilocybin (SEP-1)

This quadruple-blind, placebo-controlled trial (n=36) will investigate the role of stress response in shaping the positive effects of psilocybin (25mg or 1mg) by using metyrapone (750mg) to suppress cortisol production.

Conducted by the University of Calgary, this Phase II study will recruit healthy adults aged 22 to 65 with prior experience of altered states of consciousness. Participants will undergo four dosing sessions in random order, receiving either high-dose psilocybin (25mg) or low-dose psilocybin (1mg) in combination with metyrapone or a placebo. The study aims to determine whether suppressing the glucocorticoid stress response influences the acute or lasting effects of psilocybin, assessed through self-reports, physiological measures, and biomarkers such as cortisol, ACTH (adrenocorticotropic hormone), and BDNF (brain-derived neurotrophic factor).

Primary outcomes include changes in well-being, mood, and personality traits, measured one week after each session. Secondary outcomes will assess stress reactivity via heart rate variability, cognitive flexibility, and spontaneous thought processes. The study is expected to run from February 2025 to October 2027.

Topic Healthy Subjects Personality
Compound Psilocybin Placebo
Country Canada
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University of Calgary
The University of Calgary, located in Alberta, Canada, is a comprehensive academic and research institution.

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