Skip to content

Microdosing

The practice of taking sub-perceptual doses of psychedelics, and the evidence on whether measurable effects follow.

State of the evidence

Synthesized

Synthesized from 18 studies in the library · AI-generated, grounded in the abstracts below

Found by searching the library for Microdosing, micro-dosing, sub-perceptual dosing, low-dose psychedelics, then ranked by relevance.

The evidence on psychedelic microdosing is mixed and inconclusive. While observational and survey studies report subjective improvements in mood, cognition, and well-being, the few placebo-controlled trials find that these benefits are largely explained by the placebo effect and positive expectancy. The most rigorous meta-analyses show no significant mood benefits and a small decrease in cognitive control, indicating that any positive effects are not robustly supported by controlled research.

Confidence in the evidence

Low-Moderate
  • Only three placebo-controlled trials (article_ids 15941, 19853, 17432) exist, with small to moderate sample sizes (34–191 participants), and all show no significant between-group differences or attribute benefits to expectancy.
  • Observational and survey studies (e.g., 17070, 25833, 25830) are large but highly susceptible to bias, including self-selection, lack of blinding, and subjective reporting.
  • The umbrella review (27669) synthesizing three meta-analyses found only a small negative effect on cognitive control and no significant mood effects, with high primary-study overlap and methodological heterogeneity.
  • Preclinical evidence (27727) in rats shows no behavioral or neurogenic effects, and the systematic review (25852) notes that claims of expectancy-driven effects are premature.
  • Overall, the evidence is dominated by low-quality designs, inconsistent findings, and unresolved placebo confounds.
How we rate confidence

Confidence reflects the strength of the underlying evidence, not whether the result is favorable. It weighs the number and size of studies, their design (randomized trials count for more than observational or single-case work), how consistently they point the same way, and their risk of bias.

Tiers run from Insufficient to High. High is rare in this field: small, early, or open-label studies land lower even when their direction is encouraging.

Evidence by study

Direction is each study's finding relative to your question: Supports, Opposes, No effect, Mixed, or Unclear.

Self-blinding citizen science to explore psychedelic microdosing. 2021
No effect

All psychological outcomes improved from baseline in both microdose and placebo groups, with no significant between-group differences, suggesting anecdotal benefits are due to placebo.

RCT (self-blinding citizen science) · Sample size: 191

Exploring the effect of microdosing psychedelics on creativity in an open-label natural setting 2018
Supports

Provided quantitative support for cognitive-enhancing properties of microdosing, but authors caution that future placebo-controlled designs are needed to confirm preliminary findings.

observational (open-label natural setting)

Positive expectations predict improved mental-health outcomes linked to psychedelic microdosing 2021
Mixed

Found increased well-being and reduced anxiety/depression at 4 weeks, but positive expectancy at baseline predicted improvements, indicating a significant placebo response.

prospective observational · Sample size: 81

Motives and Side-Effects of Microdosing With Psychedelics Among Users 2019
Supports

Performance enhancement was the main motive (37%), and most reported negative effects were psychological and acute; majority were unaware of exact dose consumed.

observational (online survey) · Sample size: 1116

Microdosing with psilocybin mushrooms: a double-blind placebo-controlled study 2022
No effect

Acute effects were more intense for active dose only in participants who correctly identified their condition; no effects on creativity or cognition, with small changes toward cognitive impairment.

RCT (double-blind placebo-controlled) · Sample size: 34

Psychedelic microdosing benefits and challenges: an empirical codebook 2019
Unclear

Summarized experiences from the microdosing community to identify high-potential targets for future research, without quantitative effect estimates.

qualitative (mixed-methods codebook)

Might Microdosing Psychedelics Be Safe and Beneficial? An Initial Exploration. 2019
Supports

Reported improvements in negative moods (especially depression), positive moods, energy, work effectiveness, and health habits; also alleviation of symptoms in various conditions.

observational (descriptive reports) · Sample size: 1000

Psychedelic Microdosing: A Subreddit Analysis 2019
Mixed

Motivations included mental health self-management and cognitive enhancement; benefits reported included improved mood and creativity, but limitations included adverse effects, lack of improvement, and concerns about dependence.

observational (content analysis of Reddit)

Psychedelic Microdosing: Prevalence and Subjective Effects 2020
Supports

Microdosers attributed improvements in mood, anxiety, memory, attention, and sociability; common reasons for quitting were legal risks and difficulty obtaining substances.

observational (online survey) · Sample size: 2347

The emerging science of microdosing: A systematic review of research on low dose psychedelics (1955–2021) and recommendations for the field 2022
Mixed

Studies showed wide risk of bias; laboratory studies found changes in pain perception, time perception, and neurophysiology; self-report studies found changes in cognition and mental health; claims that effects are largely due to expectancy are premature.

systematic review

Classical psychedelic microdosing, mood, and cognitive function: An umbrella review with narrative synthesis 2026
No effect

The only significant pooled effect was a small decrease in cognitive control (d = -0.34); all other domains (including mood) were non-significant, with narrative evidence suggesting self-reported mood benefits are likely expectancy-driven.

umbrella review with narrative synthesis · Sample size: 1614

Psychedelic Use, Microdosing, Motives, and Information and Product Sources Among Young Adults in the United States 2026
Mixed

26.5% of lifetime psychedelic users had microdosed; microdosing was associated with more anxiety symptoms and adverse childhood events, and motives varied by demographics and mental health.

observational (cross-sectional survey)

Beyond Psychedelic Microdosing: Therapeutic Potential, Neuropharmacology, and Safety Considerations in Low-Dose Psychoactive Use 2026
Unclear

Argues that microdosing is not a single phenomenon and must be classified by substance class, dose-response, and evidence level; no quantitative effect estimates provided.

review (conceptual and comparative)

Clinical improvement following an integrative iboga microdosing protocol in post-concussive and hypoxic brain injury syndromes: a case series 2026
Supports

Clinical improvements were observed following an integrative iboga microdosing protocol with psychotherapy, but the design precludes causal inference.

case series · Sample size: 3

U.S. Psychedelic Use and Microdosing in 2025: Insights from a Probability-Based and Nationally Representative Survey. 2026
Unclear

Provided prevalence data on microdosing for psilocybin, LSD, and MDMA; no effect estimates reported.

observational (nationally representative survey)

Chronic psilocin microdosing produces limited behavioral effects and does not enhance neurogenesis in rats. 2026
No effect

Chronic psilocin microdosing did not affect locomotor activity, depressive-like behavior, sociability, novelty seeking, or dentate gyrus cell proliferation.

preclinical (animal study)

Characterizing Resting-State Brain Dynamics with Frequency-Resolved EEG Microstates: Parallel Analyses of Psilocybin Microdosing and Acute Inhaled DMT 2026
No effect

Psilocybin microdosing was associated with subtle EEG changes (reduced global field power, frequency-specific alterations) but no significant broadband spatiotemporal changes, indicating limited brain effects.

observational (EEG study)

A New Use for an Old Compound: Microdosing LSD to Reduce Fibromyalgia Symptoms 2026
Supports

Microdosed LSD improved pain-related behaviors and facial expressions in a sex- and route-dependent manner in a mouse model of fibromyalgia.

preclinical (animal study)

Points of agreement

  • Observational and survey studies consistently report subjective improvements in mood, well-being, and cognition from microdosing.
  • Placebo-controlled trials consistently find no significant differences between microdose and placebo groups on most outcomes.
  • Positive expectancy and placebo effects are consistently identified as major confounds across multiple study designs.
  • The most rigorous meta-analyses find no significant mood benefits and a small negative effect on cognitive control.

Conflicts

  • Observational studies report positive effects on mood and cognition, while placebo-controlled RCTs find null or expectancy-driven effects.
  • Some studies (e.g., 16309, 25833) report broad benefits, whereas others (e.g., 19853, 27727) find no effects or slight impairment.
  • The systematic review (25852) argues that expectancy explanations are premature, while the umbrella review (27669) and RCTs (15941, 17432) emphasize placebo/expectancy as the primary driver.

Gaps

  • Durability of effects beyond 4 weeks is not studied in controlled designs.
  • Blinding integrity is rarely assessed and often broken, confounding results.
  • Dose standardization and substance purity are lacking in most naturalistic studies.
  • Representative population samples are missing; most studies rely on self-selected, online convenience samples.
  • Preclinical evidence is limited and does not support behavioral or neurogenic effects.
  • No large, multi-site, fully blinded RCTs with adequate sample sizes have been conducted.
Browse these studies in the library
How we analyze this

This synthesis reads the 15 most-cited and 10 most recent studies whose primary subject is Microdosing, up to 25 in all. The most-cited set anchors the established evidence, and the recent set surfaces work that is too new to have gathered citations yet.

A study qualifies only when Microdosing or a known alias appears in its title or keywords, so broad reviews that mention it only in passing are left out. Each study is read from its abstract, strongest evidence first, and the summary reports the direction of the results along with any conflicts and gaps.

Ask your own question in the Research Synthesis Tool

363 articles · 143 from the last two years · 67,181 participants across 127 studies reporting sample size

Common study designs

review 58 qualitative study 15 systematic review 16 cross-sectional survey 16 randomized controlled trial 30

Research

Synthesize the evidence → Search all →

Data from Is It Time to Advance the Chemoprevention of Environmental Carcinogenesis with Microdosing Trials?

Thomas W. Kensler, John D. Groopman

This perspective discusses using microdosing with environmental carcinogens to speed up the testing and improvement of chemopreventive treatments. It covers the need for preventing cancer caused by environmental factors, the design of microdosing (phase 0) trials, the technologies needed for such studies, and ethical issues. It also reviews lessons learned from microdosing research so far.

DOI: 10.1158/1940-6207.c.6543726

Microdosing Is More Than Placebo In Some Individuals: A Critical Re-examination of ‘Self-blinding citizen science to explore psychedelic microdosing’

preprint

A reanalysis of Szigeti et al.'s (2021) self-blinding citizen science study on psychedelic microdosing partially supports the original conclusions but identifies specific conditions where microdosing produces positive effects compared to placebo. Positive effects were found for participants who received both placebo and treatment during their trial (affective benefits), felt some level of intoxication, correctly identified placebo from treatment, and had at least mild depression. The findings add to evidence that certain benefits may exist for psychedelic microdosing under particular circumstances.

DOI: 10.31219/osf.io/sf75q

Chronic psilocin microdosing produces limited behavioral effects and does not enhance neurogenesis in rats.

Pharmacology, biochemistry, and behavior • June 30, 2026 • Lucie Ladislavová, Viera Kútná, Kristýna Mazochová et al.

Chronic microdosing of psilocin (0.05 or 0.075 mg/kg) in adult male Wistar rats over five weeks did not alter locomotor activity, depressive-like behavior, sociability, or novelty seeking, and did not increase cell proliferation in the dentate gyrus of the hippocampus. A small anxiogenic effect was detected in the Elevated Plus Maze. The findings suggest that, under this dosing schedule, psilocin microdosing produces limited behavioral effects and does not enhance hippocampal progenitor proliferation.

DOI: 10.1016/j.pbb.2026.174231 Full text Anxiety Behavioral testing Depression Hippocampal neurogenesis +3

Classical psychedelic microdosing, mood, and cognitive function: An umbrella review with narrative synthesis

Journal of Psychopharmacology • June 28, 2026 • Yiğit Özaydın, Buket Canlan Ozaydin

An umbrella review of systematic reviews and meta-analyses on psychedelic microdosing (repeated low doses of LSD or psilocybin) for mood and cognitive effects found that the only statistically significant pooled result was a small decrease in cognitive control, contrary to popular claims of enhancement. Self-reported mood benefits were largely not replicated under placebo-controlled conditions, suggesting expectancy effects. Short-term tolerability was acceptable, but cardiovascular signals and long-term risks remain uncharacterized. The evidence base is limited by high overlap among primary studies and methodological heterogeneity.

DOI: 10.1177/02698811261456196 Mood Cognition Psilocybin Expectancy theory +6

The intersection between psychedelics and schizophrenia spectrum disorders: Reevaluating risk and therapeutic potential.

Journal of psychopharmacology (Oxford, England) • June 25, 2026 • Pavan S Brar, Rebecca B Price, Stephen Ross et al.

Psychedelic compounds like psilocybin and LSD are being studied again as potential treatments, but research usually excludes people at risk for psychosis. This narrative review examines the historical and theoretical links between psychedelics and schizophrenia spectrum disorders (SSDs), including the psychotomimetic hypothesis. The authors compare the phenomenological experiences induced by psychedelics with those of SSDs, finding both overlap and important qualitative differences that challenge a simple equivalence. They review neural mechanisms involving serotonin, dopamine, and glutamate. Clinical evidence shows psychedelics can worsen existing psychotic illness and may trigger psychosis in vulnerable individuals, though the risk magnitude is not well quantified. The authors suggest potential therapeutic applications for carefully selected symptoms in stable patients using low-dose, controlled approaches and provide recommendations for managing psychosis-related risk.

DOI: 10.1177/02698811261456191 Full text DMT LSD Mescaline Phenomenology +4

Effects of repeated low-dose LSD on neuropsychological functioning in adults with ADHD: a randomized placebo-controlled study

Psychopharmacology • June 20, 2026 • E. C. H. M. Haijen-bongers, P.p.m. Hurks, J. Schepers et al.

In adults with attention-deficit hyperactivity disorder, six weeks of biweekly low-dose lysergic acid diethylamide (20 µg) produced a limited effect on temporal processing, specifically on a time reproduction task, but did not improve performance on other neuropsychological measures of attention, inhibition, or motivational processing. The finding was observed in a secondary analysis of a double-blind, placebo-controlled trial with 46 completers. Baseline performance predicted some treatment outcomes differently between the LSD and placebo groups. The authors caution that the single positive result should be interpreted cautiously, especially because the parent trial showed no corresponding improvements in clinical symptoms.

DOI: 10.1007/s00213-026-07107-7 Full text Neuropsychology Placebo Cognition Population +9

Psychedelic Use, Microdosing, Motives, and Information and Product Sources Among Young Adults in the United States

Journal of Psychoactive Drugs • June 19, 2026 • Carla J. Berg, Darcey M. Mccready, Cassidy R. Loparco et al.

Among a sample of young adults with high rates of past-month cannabis use, lifetime and past-year psychedelic use were 27.7% and 11.9%, respectively, with psilocybin/amanita, MDMA, and LSD being most common. Nearly half used psychedelics only for nonmedical purposes. Of those who had ever used, 26.5% had microdosed. Older age, male sex, Black race, metropolitan residence, more depressive symptoms, and more adverse childhood events were linked to lifetime use. Microdosing was associated with not having children, more anxiety, and more adverse childhood events. Mental health symptoms and adverse childhood events were also tied to higher use motives, including expansion, mood enhancement, and symptom management.

DOI: 10.1080/02791072.2026.2685527 Young adult Product mathematics Substance use Addiction +2

Beyond Psychedelic Microdosing: Therapeutic Potential, Neuropharmacology, and Safety Considerations in Low-Dose Psychoactive Use

Journal of Advances in Developmental Research • June 18, 2026 • Eric P. Rubenstein

The term 'microdosing' is often treated as a single phenomenon, but it actually describes a low-dose pattern applied across many substances with different mechanisms, effects, and risks. This conceptual review classifies psychedelic and psychedelic-adjacent substances—including classical psychedelics, dissociatives, empathogens, and natural compounds—by therapeutic plausibility, pharmacological mechanism, dose-response, perceptibility, tolerance, neuroplasticity, context, and evidence strength. The article argues that without separating these factors, microdosing research cannot yield interpretable or scientifically meaningful conclusions.

DOI: 10.71097/ijaidr.v17.i1.1997 Full text Psychoactive substance Psychoactive drug Hallucinogen Experiential learning +7

Altered States, Enhanced Potential: Psychedelics and Physical Performance

June 12, 2026 • Zane Qarni, Jérémie Richard preprint

People who use psychedelics like psilocybin mushrooms and LSD often describe them as enhancing physical performance indirectly by altering attention, increasing mind-body connection, promoting flow-like absorption, and reducing pain or fatigue. Some users report greater perceived strength, speed, endurance, coordination, or overall capability, along with effortless movement, reduced self-consciousness, sharper perception, and improved focus. Reports are predominantly positive or mixed, but concerns include overexertion, injury risk, impaired judgment, and fairness in competitive settings. Psychedelics may function more as potential-enhancing substances that change the subjective conditions of performance rather than as traditional performance-enhancing drugs. Whether perceived gains correspond to measurable improvement remains unclear.

DOI: 10.31234/osf.io/txgq2_v2 Psilocybin Perception Cognition Empirical research +10

Clinical trials

All Microdosing trials →