Direct Comparison of Altered States of Consciousness Induced by LSD, Psilocybin, and DMT in Healthy Participants

Launched by UNIVERSITY HOSPITAL, BASEL, SWITZERLAND · Mar 20, 2025

Keywords

ClinConnect Summary

This clinical trial is studying the effects of three different substances—LSD, psilocybin, and DMT—on healthy people. The researchers want to find out if these substances produce similar experiences when given in controlled doses. To make sure that the timing of the effects is comparable, they will use another drug called ketanserin during the study. Participants will receive these substances in a safe environment, and the trial is currently looking for volunteers.

To be eligible for this study, participants should be fluent in German and understand the study's procedures and risks. They should be willing to follow the rules, including not using any illicit drugs during the trial and avoiding heavy machinery for 48 hours after taking the substances. Additionally, participants must have a body mass index (BMI) between 17 and 34.9. It's important to note that people with certain medical conditions, a history of serious mental health issues, or those who smoke heavily or drink excessively may not be able to participate. If you join, you can expect a close examination of how these substances might affect your state of consciousness, all while being monitored by professionals.

Gender

ALL

Eligibility criteria

• Inclusion Criteria:
• • 1. Good understanding of the German language
• • 2. Understanding of procedures and risks associated with the study
• • 3. Willing to adhere to the protocol and signing of the consent form
• • 4. Willing to refrain from the consumption of illicit psychoactive substances during the study
• • 5. Willing not to operate heavy machinery within 48 h after administration of a study substance
• • 6. Willing to use effective birth control throughout study participation
• • 7. Body mass index 17 - 34.9 kg/m2
• Exclusion Criteria:
• • 1. Relevant chronic or acute medical condition
• • 2. Current or previous major psychiatric disorder (e.g. psychotic disorder)
• • 3. Psychotic disorder or bipolar disorder in first-degree relatives
• • 4. Hypertension (SBP\>140/90 mmHg) or hypotension (SBP\<85 mmHg)
• • 5. Bradycardia (\< 45 bpm)
• • 6. Prolonged QTc interval (males: \>450 ms, females: \>470 ms)
• • 7. AV block II° (Mobitz type and Webckebach type) and III°
• • 8. Hallucinogenic substance use (not including cannabis) more than 20 times or any time within the previous two months
• • 9. Pregnancy or current breastfeeding
• • 10. Participation in another clinical trial (currently or within the last 30 days)
• • 11. Use of medication that may interfere with the effects of the study medication
• • 12. Tobacco smoking (\>10 cigarettes/day)
• • 13. Excessive consumption of alcoholic beverages (\>15 drinks/week)