Acute Subjective and Behavioral Effects of Microdoses of Lysergic Acid Diethylamide in Healthy Human Volunteers
Anya K. Bershad, Scott T. Schepers, Michael P. Bremmer, Royce Lee, Harriet de Wit
Biological Psychiatry June 3, 2019 DOI: 10.1016/j.biopsych.2019.05.019 via OpenAlex
Summary
AI-generated from the abstractSingle very low doses of LSD (6.5, 13, and 26 micrograms) produce dose-related subjective effects in healthy young adults. The highest dose (26 μg) increased ratings of vigor and slightly decreased positivity ratings of images with positive emotional content. Other mood measures, cognition, and physiological measures were unaffected. A threshold dose of 13 μg might be used safely in an investigation of repeated administrations. It remains to be determined whether the drug improves mood or cognition in individuals with symptoms of depression.
Study at a glance
| Characteristics | Double-blind, placebo-controlled, within-subjects, dose-response study Randomized Peer reviewed |
|---|---|
| Sample size | 20 |
| Population | Healthy young adults |
| Intervention | Lysergic acid diethylamide (LSD) |
| Dose | 0 (placebo), 6.5, 13, or 26 μg |
| Duration | 4 laboratory sessions at 1-week intervals; measures taken during expected peak drug effect |
| Topics | LSD |
| Keywords | Medicine Pharmacology Anesthesia Psychology |
| Citations | 176 |
| Key finding | Single microdoses of LSD produced orderly dose-related subjective effects in healthy volunteers, with 26 μg increasing vigor and slightly decreasing positivity ratings of positive images. |
Abstract
BackgroundNumerous anecdotal reports suggest that repeated use of very low doses of lysergic acid diethylamide (LSD), known as microdosing, improves mood and cognitive function. These effects are consistent both with the known actions of LSD on serotonin receptors and with limited evidence that higher doses of LSD (100-200 μg) positively bias emotion processing. Yet, the effects of such subthreshold doses of LSD have not been tested in a controlled laboratory setting. As a first step, we examined the effects of single very low doses of LSD (0-26 μg) on mood and behavior in healthy volunteers under double-blind conditions.MethodsHealthy young adults (N = 20) attended 4 laboratory sessions during which they received 0 (placebo), 6.5, 13, or 26 μg of LSD in randomized order at 1-week intervals. During expected peak drug effect, they completed mood questionnaires and behavioral tasks assessing emotion processing and cognition. Cardiovascular measures and body temperature were also assessed.ResultsLSD produced dose-related subjective effects across the 3 doses (6.5, 13, and 26 μg). At the highest dose, the drug also increased ratings of vigor and slightly decreased positivity ratings of images with positive emotional content. Other mood measures, cognition, and physiological measures were unaffected.ConclusionsSingle microdoses of LSD produced orderly dose-related subjective effects in healthy volunteers. These findings indicate that a threshold dose of 13 μg of LSD might be used safely in an investigation of repeated administrations. It remains to be determined whether the drug improves mood or cognition in individuals with symptoms of depression.