Psilocybin for Treatment of OCD-2
Key facts
- Who runs it
- Francisco A Moreno
- Where
- Tucson, United StatesSee the site
- Trial code
- Status
- Not yet recruiting
- Phase
- Phase 1/2
- People taking part
- 20 people, planned
- Started
- 8 Sept 2026
- Expected to end
- Dec 2028
- Type of study
- Interventional, 2 groupsOne group gets an existing treatment, for comparison.
- Treatments tested
- Low Dose Psilocybin
- High Dose Psilocybin
- Record updated
- 12 May 2026
Who can take part
- Age
- 18 years and older
- Sex
- Women and men
- Healthy volunteers
- Cannot take part
The registry criteria, word for word
Show all 27 criteriaShow less
Who can take part
- 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
Who cannot take part
- Concurrent active substance use disorder, or a personal history of psychosis
- Subjects cannot require any sedative, narcotic, or neuroleptic medications on a regular basis. Any of these medications they have taken should have been stopped long enough in the past to allow for their elimination and safe withdrawal prior to starting administration of the study drug. The specific time required will be dependent on the medication the patient was previously receiving
- Suicidal behavior within the 12 months prior to enrollment, or significant risk of suicide as determined by the CSSRS items 4 (suicidal ideation with intent) and 5 (suicidal ideation with intent and plan) during screening or baseline assessment
- Use within the week prior to screening of drugs of abuse as listed in the current US DOJ DEA Drugs of Abuse Resource Guide, including:
- History of psychosis among first degree relatives as determined by the Family Interview for Genetic Studies (FIGS) 32
- Medical illness based on physical examination and routine blood testing that may complicate cardiovascular safety or drug metabolism or excretion, such as uncontrolled hypertension, severe cardiac disease, or kidney or liver failure
- Unstable Chronic Obstructive Pulmonary Disease (COPD) or severe sleep apnea
- Clinically significant renal or hepatic impairment, per clinical judgment of a study physician
- Psychiatric comorbidity that may represent an acute risk to their own or other's safety
- Any condition for which MRI is contraindicated, at the discretion of a study investigator or the MRI technician, including: Pacemakers and defibrillators; artificial heart valves which are not MRI safe; any metal in head, spinal cord, eyes or chest; any electrical devices such as cochlear implants, nerve stimulators, deep brain stimulators, gastric pacemaker, or insulin or pain pumps; aneurysm clips; ferrous (i.e. non titanium alloy) implants in any part of the body
- EKG QTc ≥ 450 msec
- Women who are pregnant, breastfeeding, or unwilling/unable to practice medically acceptable highly effective birth control (double barrier, oral and injectable pharmacological contraceptives) during the study
- Cannabinoids (marijuana, synthetic cannabinoids)
- Simulants (amphetamine, cocaine, methamphetamine, methylphenidate, modafinil)
- Opioids (natural and synthetic),
- Sedatives (benzodiazepines, barbiturates, GHB, zolpidem, zaleplon, zopiclone)
- Hallucinogens (DMT, ibogaine, LSD, MDMA, psilocybin, psilocin, PSP)
Where in United States
- University of Arizona TucsonTucson, United StatesContact: Esmeralda TerrazasNot yet recruiting
About the trial
What the trial wants to find out
Previous research indicates that psilocybin, a drug that changes activity in brain areas believed to be involved in obsessive-compulsive disorder (OCD), might improve treatment for, and improve lives of, people diagnosed with OCD. The investigators propose to study 20 patients with symptomatic OCD who are not taking mind altering medications or street drugs, to participate in a 12 week study. Participants will be assigned (by luck of the draw) to take low or high dose psilocybin in four dosing sessions separated by 3 weeks. Measurements for the severity of OCD, ability to function, perception of quality of life, safety and tolerability will be measured at baseline prior to drug administration, during the dosing periods, and at the end of study. Other measurements will include brain imaging via fMRI and brain tracing via electroencephalogram (EEG). The investigators believe that during medically supervised dosing sessions, both doses of psilocybin will be safe and well tolerated, and will reduce OCD symptoms. Because psilocybin is a potent drug and especially at the higher dose may induce altered states of consciousness, a thoughtfully implemented procedure for participant safety is in place. Information will be obtained to explore the effects of altered states of consciousness in the outcome of treatment and to find the mechanism of benefit.
The 2 groups in the trial
- Low Dose psilocybin (10mg)Existing treatment, for comparison
Subjects will receive a low dose (10mg) of psilocybin at four study drug ingesting sessions. Each drug ingestion session will be separated by three weeks.
Treatment: Low Dose Psilocybin
- High dose psilocybin (30mg)Existing treatment, for comparison
Subjects will receive a high dose (30mg) of psilocybin at four study drug ingesting sessions. Each drug ingestion session will be separated by three weeks.
Treatment: High Dose Psilocybin
Questions to ask the study team
- How often do I need to come in, and for how long each time?
- Are travel costs paid?
- Can I keep my own doctor?
- What happens if I want to stop?
Contact the study team: see the registry record → Contacts and Locations
Print a page for my doctorData and sources
- Registry record
- Listed on ClinicalTrials.gov.
- Official title
- Psilocybin for Treatment of Obsessive Compulsive Disorder
- Record updated
- 12 May 2026