RecruitingPhase 1

Psilocybin Whole Mushroom for the Treatment of Obsessive-compulsive Disorder.

United States30 participantsStarted 2026-05-18

Plain-language summary

The study tries to improve our treatments for people who have obsessive-compulsive disorder (OCD) by testing psilocybin, a mind altering drug that changes activity in brain areas involved in OCD. 30 patients with moderate or more severe OCD who are not taking mind altering medications or street drugs will participate in a 12 week study. Participants will be assigned (by luck of the draw) to take a low, medium, or high dose whole psilocybin mushroom contained in three chocolate pieces, prepared for this study by the Scottsdale Research Institute.

Who can participate

Age range

18 Years

Sex

ALL

See this in plain English?

AI-rewrites the medical criteria so a patient or caregiver can understand them. Always confirm with the trial site.

Inclusion Criteria: * Aged 18 years old, and older * Have OCD (DSM-5) based on diagnostic interview using the Structured Clinical Interview for DSM-5 Research Version (SCID). * At least moderate severity: Yale-Brown Obsessive Compulsive Scale (YBOCS) score ≥16. * Failed at least one adequate trial of guideline concordant treatment. * Considered safe for independent living * Subjects must discontinue use of any of the following prescription or over the counter (OTC) products or nutritional supplements at least two weeks prior to initiating double-blind treatment: * Monoamine oxidase (MAOI), UGT1A10, and UGT1A9 inhibitors * Other active OCD treatments (cognitive behavioral therapy \[CBT\] or other psychotherapy; electrical or magnetic device treatments; pharmacological treatments such as antidepressant medications (e.g., SSRIs, SNRIs, MAOIs, TCAs, 5HT2 blockers, NERIs, etc.), lithium, antipsychotic drugs, 5-HT2 antagonists such as pimavanserin, and glutamatergic acting medications) \* Note that fluoxetine must be discontinued at least 6 weeks prior to initiating double-blind treatment. * 5HT2 agonists (e.g., efavirenz, lorcaserin), which may alter the response to psilocybin * Serotonin-acting dietary supplements (e.g., 5-hydroxy-tryptophan, St. John's wort) due to potential for interaction with psilocybin and increased safety risks Exclusion Criteria: * Concurrent active substance use disorder, or a personal history of psychosis. * History of psychosis among fi…

Questions worth asking your doctor

Bring these to your next appointment. They're a starting point for a shared conversation — not a sign you qualify or a recommendation to enrol.

1Based on my diagnosis and history, is this trial worth exploring for me — or is there a standard treatment we should try first?
2What does this trial's phase tell us about how much is already known about its safety and benefit?
3What would taking part actually involve for me — visits, tests, time, and travel?
4What are the known and possible risks or side effects I should weigh, and how would they be monitored?
5If this trial isn't the right fit, what other options or trials would you suggest I look into?

Generated to help you prepare — always confirm anything about your own eligibility and care with the study team and your doctor.

Questions for the trial coordinator

The trial coordinator is the person who runs the study day to day. These cover the practical side — logistics, costs, and what taking part would actually mean for your life. The study team confirms whether you meet the criteria; these are questions to ask, not a sign you qualify.

1What does taking part actually involve week to week — how many visits, where, and how long does each one take?
2What costs are covered by the study, and what might I have to pay for myself, including travel, parking, or time off work?
3What happens during screening, and what happens if the study team confirms I don't meet the criteria after those tests?
4Who pays for the scans, blood work, and other tests the trial requires — the study, my insurance, or me?
5How will being in the trial affect my regular care, and will my own doctor stay informed and involved?
6Can I leave the trial at any point if I change my mind, and what would happen to my care if I do?

A starting point for the conversation — always confirm anything about your own eligibility, costs, and care with the study team and your doctor.

What they're measuring

Yale Brown Obsessive Compulsive Scale

Timeframe: Baseline, Weekly for 12 weeks (Treatment phase), and Monthly for 12 month (Follow up phase).

Adverse Event (AE) Tracking log

Timeframe: Weekly for 12 weeks (Treatment phase), and Monthly for 12 month (Follow up phase).

Visual Analogue Scale (VAS)

Timeframe: Baseline, Weekly for 12 weeks (Treatment phase), and Monthly for 12 month (Follow up phase). Scale 0 (no symptoms at all) to 100 (maximum symptom severity)

Trial details

NCT IDNCT07347405

SponsorFrancisco A Moreno

Sponsor typeOTHER

Study typeINTERVENTIONAL

Primary completion2028-12-31

Contact for this trial

The clinical and translational research center

(520) 626-8000 OCD@psychiatry.arizona.edu

View on ClinicalTrials.gov More Obsessive-Compulsive Disorder trials