A Double-blind, Placebo-controlled Study to Evaluate Very Low Dose LSD in Healthy Volunteers Aged 55-75 Years

This study was a Phase I, double-blind, placebo-controlled, randomised study of very low dose LSD.

Healthy volunteers aged 55 to 75 years with no use of LSD in the past 5 years were screened within 28 days of randomization.

Subjects who met all inclusion and no exclusion criteria and provided written informed consent were randomised a 1:1:1:1 ratio to receive 6 doses of 5 µg, 10 µg, or 20 µg LSD or placebo, at 4-day intervals for 21 days (on Study Days 1, 5, 9, 13, 17, and 21).

A follow-up visit was conducted approximately 4 weeks after the last dose of LSD. A total of 48 subjects were enrolled.

Status Completed
Results Published Yes
Start date 29 June 2015
End date 05 November 2015
Chance of happening 100%
Phase Phase I
Design Blinded
Type Interventional
Generation First
Participants 48
Sex All
Age 55- 57
Therapy No

Trial Details

The magnitude of the effect of LSD was explored across specific PD measures. These included: Cognition and affect, including evaluation of memory, temporal perception, executive function, and learning Subjective effects Proprioception and balance

NCT Number NCT04421105

Sponsors & Collaborators

Eleusis is a clinical-stage life sciences company that studies and develops psychedelic drugs for therapeutic use. Since 2013 the company has been researching psychedelics and is now developing ELE-Psilo (psilocybin) for depression that is in Phase I.


The effects of microdose LSD on time perception: a randomised, double-blind, placebo-controlled trial
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Safety, tolerability, pharmacokinetics, and pharmacodynamics of low dose lysergic acid diethylamide (LSD) in healthy older volunteers
This Phase I, double-blind, placebo-controlled, randomized study (n=48) indicates that LSD administration (tested up to 20µg) didn't produce any negative effects for healthy older participants (mean age=63).

Measures Used

5-Dimensional Altered States of Consciousness Questionnaire
The 5D-ASC scale measures altered states of consciousness and contains 94 items (visual analog scales).

Data attribution

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