Four low doses of LSD in healthy adults: felt as a drug, but no lift in mood or thinking
56 healthy adults took placebo, 13 or 26 micrograms of LSD four times, three to four days apart. The higher dose was felt as a drug effect. It did not improve mood or performance, and nothing lingered after.
Well-supported by good-quality research. how we score evidence
Caveat on this rating: Four doses in healthy volunteers in a laboratory; far shorter than typical microdosing regimens.
A dose-response trial of the schedule microdosers describe, done under controlled conditions.
Significant findings
De Wit and colleagues (Addiction Biology, 2022) randomised healthy adults to placebo (n = 18), 13 micrograms of LSD (n = 19) or 26 micrograms (n = 19). Each attended four five-hour drug sessions three to four days apart, then a drug-free follow-up. The 26 microgram dose "produced modest subjective effects including increased ratings of 'feeling a drug effect' and both stimulant-like and LSD-like effects, but the drug did not improve mood or affect performance on psychomotor or most emotional tasks. No residual effects were detected on mood or task performance on the drug-free follow-up session."
The authors concluded that "repeated low doses of LSD are safe, but produce negligible changes in mood or cognition in healthy volunteers."
The other direction
Four doses is far fewer than the weeks or months many microdosers report, and the participants were healthy, so people who start with low mood could respond differently. The lab setting is the criticism the later home-dosing trial (Murphy 2023, in this library) was designed to answer. De Wit discloses advisory roles with psychedelic companies, which the paper says are not related to this study; the work was funded by the US National Institute on Drug Abuse and other public grants.
What this does not show
It does not show any benefit for depression, anxiety or focus. It does not show safety beyond four doses. LSD is not approved for any use.
Worth asking
What would a microdosing claim need to show me that this trial did not find?
Source
Repeated low doses of LSD in healthy adults: A placebo-controlled, dose-response study — de Wit H, Molla HM, Bershad A, Bremmer M, Lee R (2022)
Reputable peer-reviewed journal
Read the source: https://doi.org/10.1111/adb.13143
DOI: 10.1111/adb.13143
How this was scored
- Study design
- Randomised controlled trial
- Funding
- Independently funded
- Published in
- Reputable peer-reviewed journal
- Sample size
- 56
- Preregistered
- not recorded
- Conflicts disclosed
- Yes
- Independent of proponent
- not recorded
- Retracted
- No
Read the full scoring rubric, including what it can't tell you.
Published October 21, 2026.
Questions
How strong is the evidence behind this?
veisund rates this source "strong evidence". Well-supported by good-quality research. It scores 73 out of 100 on our published rubric. One caveat travels with that badge: Four doses in healthy volunteers in a laboratory; far shorter than typical microdosing regimens. The score is calculated from recorded facts about the source — study design, funding, publication venue, sample size, preregistration — not typed in by an editor.
What is the source for this?
Repeated low doses of LSD in healthy adults: A placebo-controlled, dose-response study — de Wit H, Molla HM, Bershad A, Bremmer M, Lee R (2022). Published in: Reputable peer-reviewed journal. DOI: 10.1111/adb.13143. The full source is linked on this page so you can read it yourself.
Who paid for this research, and does that matter?
Study design: Randomised controlled trial. Funding: Independently funded. Independence from the proponent is not recorded. Industry sponsorship is one of the most reliably measured biases in medicine, which is why funding carries real weight in the score rather than sitting in a footnote.
Is this medical advice?
This is information to bring to your prescriber, not medical advice and not a reason to change anything on your own. Nothing here is an instruction to stop or reduce a medication. If you are in crisis, call or text 988.
This is information to bring to your prescriber, not medical advice and not a reason to change anything on your own. Nothing here is an instruction to stop or reduce a medication. If you are in crisis, call or text 988.