What is Microdosing?
Microdosing is the practice of regularly ingesting very low doses of psychedelic substances—typically between one-tenth and one-twentieth of a recreational dose—with the goal of improving wellbeing, cognition, mood, or interpersonal functioning without producing hallucinogenic effects 1.
Core Definition and Dosing
The practice involves taking sub-hallucinogenic amounts of psychedelics, most commonly LSD or psilocybin, on a regular schedule (often every 3 days). While frequently described as "sub-perceptual," this terminology is somewhat misleading—many users actually report subtle subjective changes, making "sub-hallucinogenic" a more accurate descriptor 1.
Key dosing parameters:
- LSD: Approximately 5-20 micrograms (compared to 100-200 micrograms for recreational use)
- Psilocybin: Approximately 0.1-0.3 grams of dried mushrooms
- The dose should be low enough to avoid hallucinations but may produce subtle perceptible effects 1
Important Context: Two Different Meanings
Critical caveat: The term "microdosing" has two completely different meanings in medicine, and confusion between them can be dangerous:
- Psychedelic microdosing (described above): Using sub-hallucinogenic doses of psychedelics for mood/cognitive enhancement
- Pharmaceutical microdosing: A drug development technique using 1% of the pharmacologic dose or 100 µg (whichever is lower) to obtain early human pharmacokinetic data before Phase 1 trials 2, 3
These are entirely separate concepts serving different purposes.
Reported Effects and Evidence Quality
According to the most comprehensive systematic review spanning 1955-2021, microdosing studies have reported effects across six domains 1:
- Mood and mental health improvements
- Enhanced wellbeing and attitude
- Changes in cognition and creativity
- Personality alterations
- Subtle changes in conscious state
- Neurophysiological changes (pain perception, time perception)
However, the placebo effect is substantial. The largest placebo-controlled trial (n=191) found that while all psychological outcomes improved significantly during the 4-week dosing period, the placebo group improved equally, with no significant between-group differences 4. This suggests anecdotal benefits may be largely explained by expectation effects.
Safety Considerations
Recent systematic reviews identify common side effects that are typically dose-dependent, mild, and short-lived 5:
- Increased blood pressure
- Anxiety (paradoxically, given the intended use)
- Cognitive impairment
- Various physiological effects
The practice involves unregulated substances, creating three major problems 1:
- Users cannot verify drug identity or purity
- Substantial variation exists in pharmacological effects between substances, preparations, and individuals
- No standardized dosing criteria exist across different psychedelic compounds
Current Status
Microdosing gained mainstream popularity following James Fadiman's 2011 book "The Psychedelic Explorers Guide" and has since been widely discussed in media, though it remains legally prohibited in most jurisdictions 1. The practice is used both by healthy individuals seeking enhancement and those with mental health conditions, particularly depression 6, 7.
The evidence base remains limited and methodologically heterogeneous, with most studies showing wide variation in risk of bias depending on design and age 1. Claims about efficacy should be interpreted cautiously given the strong placebo effects demonstrated in controlled trials.