A systematic review of 83 studies found that subanesthetic doses of ketamine produce rapid, short-lived antidepressant and anti-suicidal effects. Evidence for other psychiatric conditions is less robust but suggests similarly positive but transient benefits. The conclusions are tentative due to high risk of bias across the included studies. Optimal dosing, administration methods, and best forms of adjunctive psychotherapy require further investigation.
Among self-selected users of a mobile app, people who microdose psychedelics (mostly psilocybin, 85%) were similar demographically to non-microdosers but more often reported a history of mental health concerns. Within that group, microdosers had lower levels of depression, anxiety, and stress across genders. Health and wellness motives were the most common reasons for microdosing, especially among women and those with mental health concerns. The findings highlight a need for rigorous longitudinal research on microdosing's mental health effects.
A naturalistic observational study followed 953 people who microdosed psilocybin (taking small, non-hallucinogenic doses of psychedelic mushrooms) and 180 non-microdosers for about 30 days. Small to medium improvements in mood and mental health were observed among microdosers, consistent across gender, age, and pre-existing mental health concerns. Older adults showed specific improvements in psychomotor performance. Combining psilocybin with lion's mane mushrooms and niacin did not affect mood or mental health changes, but among older microdosers, this combination was linked to greater psychomotor improvements than psilocybin alone or with lion's mane. These findings add controlled evidence to the growing research on psychedelic microdosing.
On days when adults microdose psychedelics, they report higher levels of wellbeing, productivity, creativity, connectedness, contemplation, and focus compared to days they do not microdose. The increase in creativity is especially pronounced among people who have previously used larger doses of psychedelics. These findings come from a large international survey of 1,435 adults who microdose, using daily-level self-reports that reduce reliance on memory. Because the study is observational and exploratory, the results should be interpreted cautiously.