Biological psychiatry
September 15, 2023
Robin J Murphy, Rachael Sumner, William Evans et al.
69 citations
Microdosing LSD (10 μg every three days for six weeks) in healthy adult men produced transient improvements in creativity, connectedness, energy, happiness, irritability, and wellness on dose days compared with nondose days, even after controlling for preintervention expectancy. However, no enduring changes in overall mood or cognition were observed between baseline and six-week assessments. The most notable adverse event was treatment-related anxiety, which led four participants in the LSD group to withdraw. Microdosing appears relatively safe in this population but does not support claims of lasting mood or cognitive benefits.
Pilot and feasibility studies
October 5, 2023
Carina Joy Donegan, Dimitri Daldegan-Bueno, Rachael Sumner et al.
23 citations
An estimated 260 million people worldwide have depression, and many self-treat with microdoses of psychedelics like LSD and psilocybin despite limited clinical evidence. A prior phase 1 study in healthy volunteers found LSD microdosing safe, well tolerated, and feasible with good adherence. This open-label pilot trial (LSDDEP1) will test tolerability and feasibility of an 8-week LSD microdosing regimen in 20 patients with major depressive disorder. Participants receive a sublingual LSD formulation (MB-22001) twice weekly at 5–15 µg. Tolerability is measured by withdrawal due to adverse events; feasibility by clinic visit attendance. Antidepressant response will be assessed with MADRS scores over 8 weeks. Results will inform a future randomized controlled trial.
Translational psychiatry
April 15, 2024
Nathan Allen, Aron Jeremiah, Robin Murphy et al.
15 citations
Microdosing LSD (10 µg every third day for six weeks) increased sleep duration in healthy adult male volunteers. On nights after dosing, the LSD group slept an extra 24.3 minutes per night compared to placebo, with no change in sleep on dosing days. Sleep stage proportions and physical activity remained unchanged. The findings indicate that microdosing LSD modifies physiological sleep requirements, and the objective changes are unlikely to be a placebo effect.
Trials
August 24, 2024
Dimitri Daldegan-Bueno, Carina Joy Donegan, Anna Forsyth et al.
14 citations
A phase 2b randomized controlled trial will test whether repeated low doses of LSD (4 to 20 micrograms, taken twice weekly for 8 weeks at home) reduce depressive symptoms in people with major depressive disorder, compared to an active placebo. The trial is triple-blind and includes measures of mood, personality, sleep, brain activity, blood biomarkers, and safety. This is the first controlled trial to test microdosed LSD in patients' natural environment. Results will help determine whether psychedelic microdosing is a viable additional treatment for depression and guide future research.
Neuropharmacology
December 1, 2025
Carina Joy Donegan, Dimitri Daldegan-Bueno, Tehseen Noorani et al.
4 citations
Before starting a low-dose LSD regimen, people with major depression held varied expectations shaped largely by media and personal experience. Over half had tried other treatments that failed. Many expected subtle effects or had no specific expectations, while some anticipated changes in consciousness or neural rewiring. Hope served both as a motivator and a buffer against disappointment. The findings underscore how media influences expectations and suggest that current expectancy measures miss important factors specific to psychedelic therapy.
Progress in Neuro-Psychopharmacology and Biological Psychiatry
February 18, 2026
Dimitri Henriques Daldegan-Bueno, C Donegan, Rachael L. Sumner et al.
1 citation
Taking very low doses of LSD (8 micrograms) repeatedly over a short period may temporarily improve mood in people with depression, though the effect needs confirmation in controlled experiments. The drug's behavior in the body was measured in this group, and no evidence of tolerance or increased sensitivity appeared, even when the dose was gradually increased.