Efficacy of Psilocybin in OCD: a Double-Blind, Placebo-Controlled Study

This study aims to investigate the effects of oral psilocybin on OCD symptomatology and provide the first evidence of the neural mechanism that may mediate psilocybin’s purported therapeutic effects on OCD.

The study protocol has been published here.

Trial Details



Trial Number

Sponsors & Collaborators

Yale University
The Yale Psychedelic Science Group was established in 2016.

National Alliance for Research on Schizophrenia and Depression
This company doesn't have a full profile yet, it is linked to a clinical trial.

Papers

Single-dose psilocybin for treatment-resistant obsessive-compulsive disorder: A case report
This pre-print case study (2022) explores the effects of single-dose psilocybin in an individual with OCD. Treatment led to improvements in OCD symptoms and positive changes to the individuals' emotions, social and work function, and quality of life.

Measures Used

Yale-Brown Obsessive Compulsive Scale
The Yale Brown Obsessive-Compulsive Scale (Y-BOSC) is considered the gold-standard to assess OCD severity. The scale consists of ten items and measures the severity and type of symptoms in people with OCD over the previous seven days. The scale is used at initial diagnosis as well as during follow up sessions after treatment. The scores range from 0 to 4, with higher scores indicating greater symptoms of OCD severity.

Montgomery-Asberg Depression Rating Scale
A ten-item diagnostic questionnaire used to measure the severity of depressive symptoms in patients with mood disorders.

Beck Depression Inventory
The Beck Depression Inventory (BDI) contains 21 self-report items, completed using a multiple-choice format. Scores range from 0-63 with higher scores associated with more severe depression.

Obsessive Compulsive Inventory-Revised
The OCI-R is an 18-item self-report questionnaire based on the earlier 84-item OCI. Participants rate the degree to which they are bothered or distressed by specific OCD symptoms in the past month.

Mystical Experience Questionnaire
The MEQ is a self-report measure that has been used to measure mystical-type experiences in laboratory studies of psychedelics. The scale was developed by Walter Pahnke in 1963 and covers the major dimensions of classic mystical experience: unity (internal and external), transcendence of time and space, noetic quality, sacredness, positive mood, and ineffability/paradoxicality. Variations of the MEQ exist; the MEQ-30 and the MEQ-43.

Data attribution

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