CompletedPhase 1

Effects of MDMA Co-administration on the Response to LSD in Healthy Subjects

NCT04516902 · LSD-MDMA · University Hospital, Basel, Switzerland

Closed to entry

Status

Not accepting participants

Phase 1

Phase

Target enrolment

Study sites

Outside the US

What it is testing

Summary

The acute subjective effects of serotonin (5-HT)2A receptor stimulation with lysergic acid diethylamide (LSD) in humans are mostly positive. However, negative effects such as anxiety, paranoid thinking or loss of trust towards other people are common effects, depending on the dose administered, the personality traits of the person consuming it (set), or the environment in which LSD is taken (setting). Negative psychedelic effects may cause acute distress to the subject and acute anxiety has been linked to less favourable long-term outcomes in patients experimentally treated with LSD or similar substances for the treatment of depression. The 5-HT and oxytocin releaser 3,4-methylenedioxymethamphetamine (MDMA) reliably induces positive mood up to euphoria, comfort, empathy, and feelings of trust. If administered in combination with LSD, MDMA may increase positive subjective drug effects including positive mood, empathy, and trust and reduce negative emotions and anxiety associated with LSD and overall produce a more positive over negative experience. The present study will assess subjective and autonomic effects of LSD alone and in combination with MDMA.

Summary as written by the trial’s own sponsor and published on ClinicalTrials.gov API v2. It is the sponsor’s description, reproduced unedited, not an assessment by this site.

What counts as success

Primary outcome measures

Acute subjective effects I
Measured over 12 months
Acute subjective effects II
Measured over 12 months
Acute subjective effects III
Measured over 12 months
Autonomic effects I
Measured over 12 months
Autonomic effects II
Measured over 12 months
Autonomic effects III
Measured over 12 months

A trial succeeds or fails on its primary outcome, declared in advance. Everything else it reports is secondary by definition.

Who can take part

Eligibility, as published

25 Years to 65 Years

Ages

All

Sex

Accepted

Healthy volunteers

Inclusion Criteria: 1. Age between 25 and 65 years old 2. Sufficient understanding of the German language 3. Understanding of procedures and risks associated with the study 4. Willing to adhere to the protocol and signing of the consent form 5. Willing to refrain from the consumption of illicit psychoactive substances during the study 6. Abstaining from xanthine-based liquids from the evenings prior to the study sessions and during the sessions 7. Willing not to operate heavy machinery within 48 h of substance administration 8. Willing to use double-barrier birth control throughout study participation 9. Body mass index between 18-29 kg/m2 Exclusion Criteria: 1. Chronic or acute medical condition 2. Current or previous major psychiatric disorder 3. Psychotic disorder or bipolar disorder in first-degree relatives 4. Hypertension (SBP\>140/90 mmHg) or hypotension (SBP\<85 mmHg) 5. Use of hallucinogenic substances (not including cannabis) more than 20 times or any time within the previous two months 6. Use of MDMA more than 20 times or any time within the previous two months 7. Pregnancy or currently breastfeeding 8. Participation in another clinical trial (currently or within the last 30 days) 9. Use of medication that may interfere with the effects of the study medication 10. Tobacco smoking (\>10 cigarettes/day) 11. Consumption of alcoholic beverages (\>20 drinks/week)

Where

1 study site

Facility	City	Region	Country
University Hospital Basel, Clinical Trial Unit	Basel	Canton of Basel-City	Switzerland

On the registry

Contact the trial directly

This site does not enrol anyone and is not involved in this trial. To ask about taking part, use the sponsor’s own contact details on the official registry record, which is also where the most current version of everything above lives.

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NCT04516902 on ClinicalTrials.gov →

Last updated in the registry 2022-08-23. Registry records change; this page reflects the data build of 2026-08-25.

Where this trial sits

Substance

All 48 trials from University Hospital, Basel, Switzerland →