Microdosing Research

This case study (n=1) describes an immunocompetent male with neuropsychiatric Lyme disease who did not respond to conventional treatments. However, his symptoms improved when he started using psilocybin in sub-hallucinogenic doses. Psilocybin is both serotonergic and anti-inflammatory, which may benefit patients with mental illness secondary to autoimmune inflammation.

This naturalistic study (n=18) on microdosing found that it led to a decrease in positive and overall emotional diversity (emodiversity). Participants experienced more “awe, wonder, or amazement” and “ashamed, humiliated, or disgraced” emotions during microdosing days and fewer “joyful, glad, or happy” emotions.

This open-label at-home study (n=25) of ketamine tablets (37.5mg) finds that repeated ‘micro’ doses led to improvements in anxiety, stress, PTSD, and depression in 90-100% of participants.

Research published in Neuroscience Applied in October 2022 suggests that microdosing may improve symptoms in adults with ADHD. The study was led by Eline C.H.M.Haijen

This double-blind placebo-controlled study (n=18) explored the effects of two microdoses of LSD (13 & 26μg) on reward processing using a monetary incentive delay task. LSD increased three reward-related ERP components, reflecting increased hedonic, motivational, and affective processing of feedback, indicating that LSD increases reward-related activity in humans.

This prospective survey study (n=247) finds that those who microdose psychedelics to manage ADHD symptoms experience benefits from it. Participants scored higher on well-being after two and four weeks. The study design, a prospective survey, makes it possible to draw causal inferences (microdosing causing the improvement), but the study had a large drop-out rate (n=46 at 4 weeks).

This pre-print reanalysed data from a placebo-controlled citizen science microdosing study (n=240) to investigate whether tolerance develops during microdosing. It was conceptualized that if tolerance develops, the probability of correctly guessing active microdoses should decrease with more microdoses. Linear regression models showed that correct microdose guess probability decreased with the number of microdoses taken (p=0.09) indicating that tolerance developed.

This paper (2022) explores the influence of macrodosing and microdosing on various clinical, social and cultural perspectives. The influence of microdosing is relatively unexplored in a formal context. Still, informal accounts propose that microdosing plays an important role as a therapeutic intervention and a cognitive enhancement tool.

This double-blind placebo-controlled study (n=34) explored the effects of microdosing psilocybin (0.5g of dried mushrooms) on subjective experience, behaviour, creativity, perception, cognition, and brain activity. In participants who correctly identified their experimental condition, the acute effects were more intense for the active dose compared to placebo. These effects were accompanied by reduced EEG in the theta band. However, no evidence supported enhanced well-being, creativity and cognitive function. Expectation likely underlies the positive effects of microdosing.

This naturalistic microdosing study used the Quantified Citizen app to assess the effects of microdosing psilocybin (n=953) compared to non-micrdosers (n=180). Small- to medium-sized improvements in mood and mental health were observed over the 30-day period. In older microdosers, combining psilocybin, lion’s mane mushrooms and niacin was associated with psychomotor improvements. These results should be taken with a grain of salt as the study lacked an adequate placebo control, and all participants were unblinded.