Microdosing psilocybin: what the research says

Microdosing means repeatedly taking small amounts of a psychedelic, such as psilocybin mushrooms or LSD, with the aim of feeling better without a full psychedelic experience. A 2026 national survey estimated that at least 8.4 million US adults have microdosed psilocybin. Improving mental and physical health were the most common reasons ^[1]. This page sets out what the research shows, and where it runs out.

The short version

• People who microdose often report better mood and less anxiety. The placebo-controlled studies below did not find a significant advantage over placebo on their main mood or well-being measures ^{[2] [3] [4] [5]}.
• Two 2026 reviews found limited evidence of benefit. One looked at healthy adults, and the other rated the evidence on mushroom and truffle microdosing as low certainty ^{[6] [7]}.
• Three placebo-controlled trials below studied people with a diagnosis: a small psilocybin trial in depression, and LSD trials in adult ADHD and in depression. None found a significant advantage over placebo on its main symptom measure. The psilocybin result is a preprint and the LSD depression result is a company press release, so neither has been peer reviewed ^{[8] [9] [10]}.
• Reported side effects include anxiety, headaches, stomach upset, poor sleep and feeling physically uncomfortable ^{[9] [17] [18]}.
• Researchers have raised a possible long-term risk to heart valves with repeated use. It has not been shown in people ^{[24] [26]}.
• Psilocybin is a Schedule I drug under federal law and Montana law ^{[33] [34]}.

What the controlled studies found

Placebo did about as well. A 2021 study was completed by 191 people with previous psychedelic experience who planned to microdose. They used their own substances, and a method designed to hide whether each capsule held a microdose or a placebo. Most used LSD or a similar drug, and about a quarter used psilocybin mushrooms. Mood and well-being improved over four weeks in both groups, with no significant difference between them. The authors concluded that placebo can explain the benefits people report ^[2].

Two more trials found the same pattern. A 2022 placebo-controlled study in Argentina included 34 people planning to microdose with mushrooms. Microdosing did not improve well-being, creativity or thinking, and showed a few small changes toward worse thinking ^[3]. A 2022 Dutch trial of psilocybin truffles found no effect on anxiety, depression or how people processed emotion, compared with placebo ^[4].

Results differ by outcome. Two placebo-controlled trials of psilocybin truffles, published in 2026, found no significant effect on thinking, mood or well-being. Participants mostly described their experience as positive whether they took psilocybin or placebo, and those taking psilocybin reported more unpleasant bodily feelings ^[5]. Another 2026 analysis of three placebo-controlled trials found more original answers on a creative thinking task, while other creativity measures did not change. That does not show a treatment benefit ^[11].

Trials in people with a diagnosis. In a small trial of 39 adults with mild to moderate depression, depression scores fell by a similar amount whether people took psilocybin or a placebo. No serious adverse events were reported during treatment. This result was posted in February 2026 as a preprint, which has not yet been peer reviewed ^[8]. In a 2025 trial in Switzerland and the Netherlands, 53 adults with ADHD took low-dose LSD or a placebo for six weeks. ADHD symptoms improved in both groups, with no difference between them. The LSD group reported 124 adverse events, compared with 64 in the placebo group. These were health problems recorded during the trial, not all proven to be caused by LSD. No serious adverse events were reported, and two people stopped because the effects were uncomfortable or got in the way of daily life ^[9]. In November 2025, the company MindBio reported that depression scores improved in both groups of its 89-person LSD trial, with no significant difference between LSD and placebo. That result comes from a company press release ^[10].

Expectations matter. In several trials, many participants could tell whether they had taken the active dose ^{[2] [3]}. In the 2021 study, people who believed they had taken a microdose reported better results than people who believed they had taken a placebo, whichever capsule they actually took ^[2]. A separate 2021 study found that people who expected more from microdosing reported more improvement in well-being ^[13]. Some researchers argue it is too early to call microdosing a placebo, in part because most controlled studies were done in healthy volunteers rather than people with a diagnosis ^[12].

What the surveys found

People report feeling better, but these studies cannot show why. A 2022 study followed 953 people who microdosed psilocybin and 180 who did not for about a month, using a phone app. The microdosers reported small to medium improvements in mood and mental health. Everyone knew which group they were in and chose to take part. Some authors had commercial ties to the app or to mushroom supplement businesses ^[14]. An earlier survey of more than 8,000 people found lower anxiety and depression among microdosers with mental health concerns. The authors say this should be read with caution until it is repeated ^[15].

ADHD. In a 2022 study, people using microdosing on their own for ADHD reported fewer symptoms after four weeks, but more than three in four had dropped out by then, and there was no placebo group ^[16]. The controlled LSD trial in adult ADHD found no benefit over placebo ^[9].

Lion's mane and niacin. Some people take psilocybin with lion's mane mushroom and niacin. In the app study, adding them did not change mood or mental health results. A finding about finger-tapping speed in people aged 55 and older was based on small groups, and the authors say it needs to be repeated. One author sells lion's mane products and has applied for patents on this combination ^[14].

Menopause. The research reviewed for this page does not show whether microdosing psilocybin helps menopause or perimenopause symptoms.

What the research does not show

• It does not show that microdosing treats depression, anxiety or ADHD. Controlled results vary by substance, by who was studied and by what was measured ^{[6] [7] [8] [9]}.
• It does not show long-term safety. Most trials lasted weeks. Many surveys did not ask about side effects ^[7].
• It says little about people taking antidepressants. A review published in 2026, covering research through June 2024, found no study that tested psilocybin microdosing in people taking an SSRI ^[23]. A 2024 case report described serotonin toxicity in a woman who was microdosing mushrooms while taking several antidepressants, and the authors could not tell how much psilocybin contributed ^[22]. Do not stop or change a prescribed medication without your prescriber. Our page on psilocybin and SSRIs covers this question.
• It does not tell you what is in a mushroom. Labs that measured psilocybin across many mushrooms found that the amount varies widely between species, between collections and between individual mushrooms ^[20]. In one study of preserved research specimens, some had no detectable psilocybin or psilocin ^[21].

Reported side effects and risks

Common complaints. In a survey of 1,116 people who microdosed, about one in five reported a negative effect, mostly around the time they took it. The most common reason people gave for stopping was that it did not work ^[18]. In another survey, people described physical discomfort, including poor sleep, stomach upset, headaches, feeling too hot or cold, and tingling, along with more anxiety ^[17]. A controlled LSD study in healthy men found short-term improvements in some mood measures, but no lasting change on questionnaires or thinking tasks. Four people left the LSD group because of anxiety ^[19].

Heart valves. Psilocin, the active form of psilocybin, acts on a serotonin receptor known as 5-HT2B. Some older medicines that acted on that receptor and were taken regularly, such as fenfluramine and pergolide, damaged heart valves. A 2024 review concluded that repeated microdosing may carry a similar risk and should be studied, and it noted that the long-term effects on the heart are unknown ^[24]. A 2026 study of nearly 287,000 US adults found slightly higher odds of heart valve disease in people who had ever used any hallucinogen. It did not separate psilocybin from other drugs and had no information on microdosing ^[25]. A 2026 review described the heart valve concern as a reasonable hypothesis, not a proven problem in people ^[26].

Mental health history. Psilocybin research usually excludes people with a personal or family history of psychosis or bipolar disorder, so little is known about the risks for them ^[26].

Lithium. An analysis of 62 online reports involving lithium and a classic psychedelic found seizures in 47% of them. It left out microdosing reports, so the figure cannot estimate the risk from microdosing. The reports were unverified, and the authors still advise people taking lithium to avoid classic psychedelics ^[27].

Store-bought "microdosing" products. In 2024, an outbreak involving Diamond Shruumz and other mushroom-containing chocolates and gummies caused 180 reported illnesses in 34 states. Among people with known outcomes, 43.7% were hospitalized, and the CDC reported two associated deaths ^[29]. The FDA's investigation listed three cases in Montana and three potentially associated deaths. Its tests found ingredients that varied between products, including muscimol, a compound from a different kind of mushroom, and the prescription drug pregabalin. Diamond Shruumz products were recalled and should not be eaten ^[28]. These findings concern commercial products with uncertain contents and do not isolate the effects of psilocybin ^{[28] [29]}. The CDC warns that microdosing psychedelic products can cause severe illness or death ^[29].

When to get help

Call 911 if someone collapses, has a seizure, has trouble breathing or cannot be woken up. Chest pain and sudden confusion are also emergencies ^{[30] [31]}. For a possible poisoning without those signs, call Poison Control at 1-800-222-1222 ^[30].

Talk with your doctor or prescriber before trying anything that could interact with your medications or health conditions, and tell them honestly what you are considering.

For support during or after a hard experience, the Fireside Project runs a free, confidential peer support line. Call or text 62-FIRESIDE (623-473-7433), any day from 11 a.m. to 11 p.m. Pacific, which is noon to midnight in Montana. It is emotional support, not medical care, and it is not a suicide hotline ^[32]. For thoughts of suicide or a mental health crisis, call or text 988, any time ^[31].

Where the law stands

Psilocybin and psilocin are Schedule I controlled substances under federal law and under Montana law, which lists them by name ^{[33] [34]}.

In August 2026, Compass Pathways said it expected to finish its FDA application for COMP360, its synthetic psilocybin treatment for treatment-resistant depression, by the end of the year. It said a launch could come in the first half of 2027, if the FDA approves it and the DEA reschedules psilocybin. That research is separate from microdosing ^[35].

What is being studied now

A registered placebo-controlled trial is studying psilocybin microdosing for distress in people receiving palliative care ^[36].

Common questions

Does microdosing mushrooms help depression or anxiety?

People who microdose often report feeling better. The controlled studies on this page did not show a benefit over placebo for depression or anxiety ^{[2] [3] [4]}. In a small placebo-controlled trial of psilocybin microdosing in people with depression, both groups improved by a similar amount. That result has not yet been peer reviewed ^[8].

Does microdosing help ADHD?

The placebo-controlled trial in adults with ADHD described above used LSD, and it found no benefit over placebo on ADHD symptoms ^[9]. Studies of people microdosing on their own for ADHD had no placebo group ^[16].

What are the side effects of microdosing mushrooms?

People report anxiety, headaches, stomach upset, poor sleep and physical discomfort ^{[17] [18]}. Researchers have also raised a possible long-term risk to heart valves, which has not been shown in people ^{[24] [26]}. Products sold as microdosing chocolates and gummies have caused serious illness ^[29].

Is microdosing psilocybin legal?

Not in Montana, and not under federal law. Psilocybin is a Schedule I controlled substance under both, and there is no exception for small amounts ^{[33] [34]}.