Effect of Ketanserin, Olanzapine, and Lorazepam After LSD Administration on the Acute Response to LSD in Healthy Subjects (LBL)

This randomized, quadruple-blind, crossover trial (n=20) conducted by the University Hospital in Basel, Switzerland, aims to investigate the effect of ketanserin (40 mg), olanzapine (10 mg), and lorazepam (2 mg) administered after LSD (150 µg) intake on the acute response to LSD in healthy subjects.

LSD is being explored as a potential treatment for various psychiatric and somatic disorders, and its use is gaining attention in therapy. The study seeks to determine if these medications can attenuate and shorten the LSD response compared to LSD alone. Additionally, it aims to understand changes in the quality of the LSD experience and effects on sensorimotor gating and sleep.

The study’s primary purpose is basic science, and it follows a randomized, crossover design. Participants, aged between 25 and 65, are required to have a sufficient understanding of the German language and must adhere to the study protocol. They will be assessed for various outcomes, including alterations in consciousness, subjective effects, psychotomimetic effects, blood pressure, heart rate, body temperature, pupil size, and concentrations of LSD and medications in the blood plasma. The study began on February 1, 2024, and is estimated to be completed by June 30, 2025.

Topic Healthy Subjects
Compound LSD
Country Switzerland
Visit trial
Status Recruiting
Results Published No
Start date 01 February 2024
End date 30 June 2025
Phase Phase I
Design Blinded
Type Interventional
Generation Second
Participants 20
Sex All
Age 25- 65
Therapy No

Trial Details

The main objective of this study is to determine whether administration of ketanserin (40 mg), olanzapine (10 mg), and lorazepam (2 mg) after administration of LSD (150 µg) attenuates and shortens the subjective LSD response (any drug effect) compared to administration of LSD (150 µg) alone

NCT Number NCT05964647

Sponsors & Collaborators

University of Basel
The University of Basel Department of Biomedicine hosts the Liechti Lab research group, headed by Matthias Liechti.

Data attribution

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