Microdosing psilocybin: what the research shows

Microdosing means taking a very small amount of a psychedelic, below the level that causes noticeable perceptual effects, repeatedly over weeks or months. People who do it usually describe it as a way to improve mood, focus or creativity. The research question is simple to state and hard to answer: do those benefits come from the drug, or from the expectation of them?¹

There's no standard definition. A 2026 systematic review of mushroom and truffle microdosing found the amounts and schedules used in studies were extremely varied, which makes results hard to compare.²

What surveys and observational studies report

Studies that follow people who are already microdosing tend to find improvements.

• A 2019 study tracking 98 microdosers for six weeks found better psychological functioning on dosing days and lower depression and stress by the end, but also a rise in neuroticism. What participants expected didn't match what they actually reported.³
• A 2021 web-based study found well-being improved and anxiety and depression fell, but people's positive expectations at the start predicted those improvements, which the authors said suggested a significant placebo response.⁴
• Two large app-based studies found that microdosers with mental health concerns reported lower anxiety, depression and stress than non-microdosers (4,050 microdosers compared with 4,653 non-microdosers), and that 953 psilocybin microdosers showed small-to-medium improvements in mood over about a month compared with 180 non-microdosers.^5,6

None of these studies had a placebo group, so they can't separate the drug's effect from expectation. People who have a good experience may also be more likely to keep microdosing and to stay in a study. The two app-based studies also disclose that the data platform and some co-authors had commercial ties, including a co-author who is an investor and patent applicant for psilocybin combination products.^5,6

What placebo-controlled studies found

When participants don't know whether they've taken psilocybin or a placebo, most of the benefits shrink or disappear.

The LSD trials, for context

The largest controlled microdosing trials have used LSD rather than psilocybin. In a 2023 trial of 80 healthy men, mood ratings rose on dosing days compared with non-dosing days, even after accounting for expectations, but there was no lasting change in mood or cognition after six weeks, and four participants withdrew because of anxiety.¹³ The same trial found no effect on objective creativity tests, even though participants felt more creative.¹⁴ A 2024 review of 14 controlled lab studies concluded that low doses had measurable short-term effects on blood pressure, sleep, brain connectivity and mood, but repeated doses didn't change mood or cognition.¹⁵ An open-label 2026 study of LSD microdosing in 19 people with depression reported large symptom reductions, but without a placebo group.¹⁹

How reviewers read the evidence

Reviewers don't all agree. A 2024 review of 19 placebo-controlled studies found that microdosing does produce measurable changes compared with placebo in the body, brain, mood and thinking, and argued that calling microdosing "just placebo" is premature: the studies are few and small, mostly use healthy volunteers, and may have used amounts that were too low. Its conclusion was that it isn't yet possible to say whether microdosing is a placebo.¹

A 2026 systematic review limited to mushroom and truffle microdosing, covering 11 studies and 3,262 adults, rated the certainty of evidence as low and said a causal effect can't be inferred. It also found that side effects were under-reported.² Researchers have also pointed out that trials rarely report the mindset and setting in which people microdose, even though those factors shape psychedelic effects.¹⁸

The heart-valve question

Some drugs that activate a serotonin receptor called 5-HT2B have caused heart-valve damage when taken for long periods. Psilocybin and its metabolite psilocin also bind that receptor. A 2023 analysis concluded that valvular heart disease is a potential risk with chronic psychedelic microdosing, though its safety margins appeared wider than those of drugs known to damage valves. The authors found no animal or human studies designed to test the risk.¹⁶ A separate review found there isn't enough evidence on the cardiac safety of microdosing.¹⁷ This is a theoretical concern, not a demonstrated harm, but it's the kind of risk that only shows up after long-term use.

What's still unknown

• Whether benefits exceed placebo for people with depression or anxiety, as opposed to healthy volunteers. Clinical trials are still small, and a 2026 trial in people with depression, still a preprint, found no difference from placebo.¹²
• Long-term safety of repeated use over months or years, especially for the heart.^16,17
• How much blinding matters. When people can tell they've taken the active dose, effects look bigger.^7,8
• What "a microdose" even is. With potency varying widely between mushrooms, studies rarely compare like with like.²

Retailers also publish practical guides. If you read one, such as My Mushroom Dispensary's microdosing guide or its page on what microdosers commonly report, it's worth comparing its claims with the controlled studies above. For interactions and who should avoid psilocybin, see our safety guide.