Psilocybin safety and tolerability in healthy adults ages 65–85

A Multicenter Phase 1 Safety and Tolerability Trial of Psilocybin in Healthy Older Adults

Phase 1 Interventional University of Colorado, Denver · NCT07516405

This project will test whether two oral doses of psilocybin given one month apart are safe and tolerable for generally healthy adults aged 65 to 85.

Quick facts

PhasePhase 1
Study typeInterventional
Enrollment40 (estimated)
Ages65 Years to 85 Years
SexAll
SponsorUniversity of Colorado, Denver Academic / other
Locations6 sites (San Francisco, California and 5 other locations)
Trial IDNCT07516405 on ClinicalTrials.gov

What this trial studies

This Phase 1 study enrolls healthy volunteers aged 65–85 and gives two oral doses of psilocybin in one of two dose schedules (moderate: 10 mg then 25 mg; high: 15 mg then 30 mg) spaced 30 days apart. Participants are closely monitored for vital signs, heart rhythm, mental status, and adverse events during and after dosing, with blood sampling to measure how the body absorbs and clears psilocybin. The study also collects patient-reported measures of mood, cognition, and the psychedelic experience to explore relationships between drug levels, safety signals, and subjective effects. Safety and tolerability in these older adults will determine whether future clinical research in this age group is appropriate.

Who should consider this trial

Good fit: Generally healthy adults aged 65–85 who can give informed consent, have an identified support person, and do not have unstable medical or excluded psychiatric conditions are ideal candidates.

Not a fit: People with uncontrolled hypertension, significant CNS disease, primary psychotic or serious bipolar disorders, active substance use disorders, extensive prior serotonergic hallucinogen use, or who take contraindicated serotonergic or interacting medications are unlikely to benefit or be eligible.

Why it matters

Potential benefit: If shown to be safe and tolerable, this work could open the door to future research of psilocybin-based therapies for older adults and improve understanding of dosing and monitoring needs in this age group.

How similar studies have performed: Previous psilocybin studies in younger or clinical populations have generally shown tolerability and informative pharmacokinetics, but dedicated safety data specifically in healthy older adults are limited.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

* Aged 65-85 years \& be male, female, or non-binary
* Generally healthy
* Have an identified support person
* Capacity to Consent

Exclusion Criteria:

* Unstable medical condition
* Risk for hypertensive crisis (screening blood pressure \>140/90 mmHg)
* Significant central nervous system (CNS) pathology
* Primary psychotic or affective psychotic disorders
* Family history of psychotic or serious bipolar spectrum illnesses
* High risk of adverse emotional or behavioral reaction
* Active substance use disorders (SUDs)
* Extensive use of serotonergic hallucinogens
* High risk of completed suicide
* History of hallucinogen persisting perception disorder (HPPD)
* Concurrent Medications: centrally-acting serotonergic agents; antipsychotics; certain mood stabilizers, aldehyde dehydrogenase inhibitors; significant inhibitors of UGT 1A9 or UGT 1A10
* Certain psychiatric conditions
* Presence of relevant finding (psychological, physical symptom, medication) prior to dosing that would make a participant unsuitable for the study

Where this trial is running

San Francisco, California and 5 other locations

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
Conditions Healthy VolunteerOlder Adultshealthy older adults ages 65-85psilocybin safetypsilocybin tolerability
Last reviewed 2026-06-13 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.