for people ages 25-50 (full criteria)
Healthy Volunteers
healthy people welcome
at San Francisco, California
study started
completion around
Principal Investigator
by Joshua Woolley, MD/PhD
Headshot of Joshua Woolley
Joshua Woolley



To compare the physiological and psychological effects of psilocin taken orally by pill or sublingually by dissolving a tablet under the tongue to those of psilocybin taken by pill in healthy adults.

Official Title

Comparison of the Effects of PEX20 (Oral Psilocin), PEX30 (Sublingual Psilocin), and PEX10 (Oral Psilocybin) in Healthy Adults


The primary goal of this study is to compare the physiological and psychological effects of psilocin taken orally by pill or sublingually dissolved under the tongue to those of psilocybin taken by pill. Twenty participants, ages 25 to 50, with one previous experience with psychedelics, and who meet all other inclusion and exclusion criteria at screening will be enrolled. After baseline assessments, participants will engage in preparatory visits with trained facilitators, followed by drug administration, supervised by the facilitators and a clinician who will conduct safety monitoring throughout. Participants will then complete assessment and integration sessions with the facilitators in order to help process the experience. The same preparation, procedures, integration, and supervision will be repeated up to three more times with each participant.


Healthy, Psilocybin, Psilocin, Psilocybin Therapy, Psychedelics, San Francisco, Sublingual Psilocin, Oral & Sublingual Psilocin, & Oral Psilocybin


You can join if…

Open to people ages 25-50

  • Age 25 to 50
  • Comfortable speaking and writing in English
  • Commit to attending all study visits and remote data collection tasks
  • No planned surgeries during the study
  • Had at least one prior experience with a psychedelic substance
  • Generally mentally and physically healthy
  • Agree to abstain from THC, CBD, or nicotine products during study

You CAN'T join if...

  • Participated in another clinical trial within 30 days of entry to this trial
  • Regular use of medications that may have problematic interactions with psilocybin, including but not limited to dopamine agonists, MAO inhibitors, N-methyl-D-aspartate (NMDAR) antagonists, antipsychotics, and stimulants
  • A health condition that makes study unsafe or unfeasible, determined by study physicians


  • UCSF accepting new patients
    San Francisco California 94143 United States

Lead Scientist at UCSF

  • Joshua Woolley, MD/PhD
    Dr. Josh Woolley is an Associate Professor in Residence in the Department of Psychiatry and Behavioral Sciences at the University of California, San Francisco (UCSF) as well as a staff psychiatrist in Mental Health at the San Francisco Veterans Affairs Medical Center (SFVAMC). He is Board Certified in Psychiatry by the American Board of Psychiatry and Neurology.


accepting new patients
Start Date
Completion Date
University of California, San Francisco
Individuals interested in participating in the clinical trial, please notify the study team of interest by completing the pre-screening survey on the website located under the specific study heading.
Phase 1 Psilocybin Research Study
Study Type
Expecting 20 study participants
Last Updated