Fig. 2: Acute subjective effects induced by lysergic acid diethylamide (LSD) and psilocybin over time on the Visual Analog Scale (VAS).

LSD (100 or 200 µg), psilocybin (15 or 30 mg), or placebo was administered at t = 0 h. Generally, the LSD doses of 100 µg and 200 µg and psilocybin dose of 30 mg produced comparable subjective effects on the VASs “any drug effect,” “good drug effect,” “bad drug effect,” “drug liking,” “feeling high,” “feeling stimulated,” and “fear.” Only the VAS “ego dissolution” showed a significant difference between 100 and 200 µg LSD. The high 30 mg psilocybin dose produced maximal subjective effects that were comparable to 100 and 200 µg LSD, with no significant differences on any of the VASs. The 30 mg psilocybin dose produced significantly greater peak responses than the 15 mg psilocybin dose on the VAS “any drug effect,” “good drug effect,” “feeling stimulated,” and “ego dissolution.” The data are expressed as the mean ± SEM percentage of maximally possible scale scores in 28 subjects. The corresponding maximal responses and statistics are shown in Supplementary Table S3.