Microdosing Psychedelics: Current Evidence From Controlled Studies.

Taking regular low doses of psychedelic drugs (microdosing) has drawn attention for potential psychotherapeutic effects, but controlled studies have lagged. A review of 14 rigorous double-blind placebo-controlled studies using investigator-supplied lysergic acid diethylamide (LSD) at 5-20 micrograms found that acute microdoses dose-dependently altered blood pressure, sleep, neural connectivity, social cognition, mood, and perception of pain and time. Perceptible drug effects occurred at 10-20 micrograms but not 5 micrograms. No serious adverse effects were reported. Repeated doses did not alter mood or cognition on any measures. Low doses of LSD appear safe and produce acute behavioral and neural effects in healthy adults, warranting further study in patient samples and with other psychedelics.

Study at a glance

Abstract

Taking regular low doses of psychedelic drugs (microdosing) is a practice that has drawn recent scientific and media attention for its potential psychotherapeutic effects. Yet, controlled studies evaluating this practice have lagged. Here, we review recent evidence focusing on studies that were conducted with rigorous experimental control. Studies conducted under laboratory settings using double-blind placebo-controlled procedures and investigator-supplied drug were compiled. The review includes demographic characteristics of participants and dependent measures such as physiological, behavioral, and subjective effects of the drugs. Review criteria were met by 14 studies, all of which involved acute or repeated low (5-20 μg) doses of lysergic acid diethylamide (LSD). Acute microdoses of LSD dose-dependently altered blood pressure, sleep, neural connectivity, social cognition, mood, and perception of pain and time. Perceptible drug effects were reported at doses of 10 to 20 μg but not 5 μg. No serious adverse effects were reported. Repeated doses of LSD did not alter mood or cognition on any of the measures studied. The findings suggest that low doses of LSD are safe and produce acute behavioral and neural effects in healthy adults. Further studies are warranted to extend these findings to patient samples and to other psychedelic drugs and to investigate microdosing as a potential pharmacological treatment for psychiatric disorders.