A Randomized Double-masked Dose-controlled Trial to Assess the Tolerability, Safety, Subjective Experience, and Efficacy of Repeated Administration of Three Different Doses of Psilocybin Whole Mushroom for the Treatment of Obsessive-compulsive Disorder.
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.
• 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