Pharmacokinetics and Pharmacodynamics of Lysergic Acid Diethylamide Microdoses in Healthy Participants.

The higher 20 μg dose of LSD base that was used in the present study and the equivalent 26 μg dose of LSD tartrate that was used previously 17 both induced weak but clearly significant subjective effects compared with placebo under double‐blind controlled conditions. 17 These data indicate small but measurable psychedelic‐like effects at a 20 μg LSD base equivalent. 17 Thus, 20 μg LSD base could be considered a very low to low psychedelic dose.

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