Psilocybin and Pindolol Study for Psychedelic Effects
This study is looking at how the drug psilocybin affects healthy volunteers, specifically how it changes your perceptions and experiences. Researchers want to see if another drug called pindolol, which blocks a specific brain receptor (5-HT1A), changes these effects. You might be able to join if you are a healthy adult between 21 and 60 years old, have a high school education, and are fluent in English. The main goal is to measure changes in "mystical experiences" using a questionnaire over about 10 days. The study is currently unclear on its recruitment status.
- Study design
- This is a double-blind, randomized, cross-over study with 18 participants. This means neither you nor the researchers will know if you're receiving psilocybin with pindolol or a placebo, and you will receive different treatments at different times.
- What's involved
- You will have two drug administration sessions. You will also complete sleep and dream diaries for 10 days before and 10 days after each drug session, and wear an at-home sleep EEG device for 5 days before and 5 days after each drug session.
- Compensation
- Not stated in the trial record.
- Follow-up
- Your mystical experiences will be measured from the first dosing session to the end of the second dosing session, approximately 10 days.
AI-generated from the public study record. Only the study team can confirm whether you're eligible — confirm details with them before making decisions.
NCT07565493
Psilocybin Administration With 5-HT1a Blockade
Recruiting
EARLY_PHASE1Ages 21–60InterventionalBasic scienceJohns Hopkins UniversityInvestigator-initiated
~18 participants
Updated 2026-08-14 on ClinicalTrials.gov
What's tested:PindololPlaceboPsilocybin
At a glance
Recruiting sites
1 of 1 listed site is recruiting right now
RecruitingSuspended, closed, or not yet open
What they're measuring
Mystical Experiences Questionnaire
Measured over From the first dosing session to the end of the second dosing session, approximately 10 days
Conditions
Where it's being run
1 sites across 1 statesMaryland1
Study leadership
- Sandeep M Nayak, MD · PRINCIPAL_INVESTIGATOR · Center for Psychedelics and Consciousness Research
Who to contact
Opens a ready-to-send draft in your own email app — review before sending.
Do you actually qualify for this trial?
Add a private profile and we'll compare every criterion below against your situation — and tell you which ones are met, uncertain, or excluding.
Eligibility criteria
Inclusion
21 - 60 years old
Must give written or electronic informed consent
Must have at least a high-school level of education or equivalent (e.g. GED) and are fluent in English
Must be healthy and psychologically stable as determined by screening for medical and psychiatric problems via a personal interview, a medical questionnaire, a physical examination, an electrocardiogram (ECG), and routine medical blood and urinalysis laboratory tests
Must agree not to take any as needed (PRN) medications on the mornings of drug sessions
Must agree not to take sildenafil (Viagra®), tadalafil, or similar medications within 72 hours of each drug administration.
Must agree to refrain from using all psychoactive substances within 24 hours or 5 elimination half-lives (whichever is greater) before psilocybin administration. Caffeine is the exception.
Must have a negative urine toxicology report on the same day as drug dosing.
Who are female and of child-bearing potential and are sexually active, must agree to use highly effective means of birth control (i.e. implants, injectables, combined oral contraceptives, progestin-containing intrauterine device (IUD) or vasectomized partner) for the duration of this study.
Who are male and sexually active, must agree to use contraception and refrain from sperm donation within 90 days of completing dosing sessions. Effective methods of contraception are barrier, hormonal, and sterilization methods.
Exclusion
Are currently taking a medication with any significant pharmacokinetic or pharmacodynamic interactions with pindolol (e.g. beta-blockers or other anti-hypertensive medications).
Have a history of orthostatic hypotension or low blood-pressure.
Have elevated transaminases (2x the upper limit of normal)
Have a Child-Pugh score that falls within classes B or C.
Are pregnant (as indicated by a positive urine pregnancy test assessed at intake and before each drug session) or nursing.
Have cardiovascular conditions: coronary artery disease, stroke, angina, uncontrolled hypertension, a clinically significant ECG abnormality (e.g. atrial fibrillation, corrected QT interval (QTc) \> 450 msec), artificial heart valve, symptomatic valvopathy, history of pulmonary hypertension or transient ischemic attack (TIA) in the past year; systolic blood pressure \> 139, diastolic blood pressure \> 89
Have epilepsy or a history of seizures
Have insulin-dependent diabetes; if taking oral hypoglycemic agent, then no history of hypoglycemia
Are currently taking on a regular (e.g. daily) basis any medications having a centrally acting serotonergic effect, including monoamine oxidase inhibitors (MAOIs). For individuals who have intermittent or PRN use of such medications, psilocybin sessions will not be conducted until at least five half-lives of the agent have elapsed after the last dose.
Have a current diagnosis of schizophrenia spectrum disorders
Have a current diagnosis of bipolar spectrum disorders
Have a current diagnosis of major depressive disorder or Generalized Anxiety Disorder
Have a current diagnosis or history of substance induced psychotic disorder
Have a current DSM-5 moderate or severe alcohol or drug use disorder (excluding caffeine and nicotine)
Have a first degree relative with bipolar I disorder, or schizophrenia spectrum disorder.
Have a psychiatric condition judged to be incompatible with establishment of safe exposure to psilocybin.
Have a BMI ≥ 40
Report a known history of sleep apnea, symptoms indicative of sleep apnea, or have an Apnea-Hypopnea Index (AHI) \> 15, or STOP BANG \>5
Taking prescribed hypnotics or other medications known to alter sleep physiology: i.e., Z-drugs, Benzodiazepines, Orexin Agonists or Antagonist, Beta Blockers.
Regularly taking over-the-counter sleep aids (inc. melatonin and diphenhydramine) and unwilling to abstain during the study.
Insomnia Severity Index ≥ 10
What this trial measures
- Mystical Experiences QuestionnaireFrom the first dosing session to the end of the second dosing session, approximately 10 days
Assess changes in intensity of the subjective effects induced by psilocybin with co-administration of a 5-HT1A antagonist, pindolol as measured through the mystical experience questionnaire. Scores can range from 0-150 with a higher score indicating a more intense mystical-type experience.