Most of the research on microdosing is observational,. This means it does not directly prove that microdosing causes the observed benefits.

Side effects, such as nausea, anxiety, and headaches have also been reported by people to occur after microdosing psilocybin. However, these side effects are safe, usually mild and are not long lasting.

Side effects:

Conceivable Side Effects of Microdosing
Headaches
Nausea
Dizziness
Anxiety
Mood fluctuations
Hallucinatory experiences

Sources:

• Microdoses of psychedelic mushrooms may improve mood and mental health. Medical News Today. https://www.medicalnewstoday.com/articles/microdoses-of-psychedelic-mushrooms-may-improve-mood-and-mental-health
• Effects of microdosing psilocybin on mood, anxiety, and cognitive function. Nature. https://www.nature.com/articles/s41598-021-01811-4
• Why some moms microdose mushrooms for anxiety, depression. The Washington Post. https://www.washingtonpost.com/wellness/2023/02/08/microdosing-mushrooms-anxiety-depression-moms/
• More People Are Microdosing for Mental Health. But Does It Work?. The New York Times. https://www.nytimes.com/2022/02/28/well/mind/microdosing-psychedelics.html
• Eight months ago I started microdosing shrooms to relieve crippling anxiety and depression. It’s working.. The Colorado Sun. https://coloradosun.com/2022/08/07/microdosing-shrooms-psilocybin-anxiety-depression/