Open-label trial · 2025
Capsules combining DMT and harmala alkaloids produced strong altered states in 9 volunteers
- Original title
- Acute experiences and persisting psychological effects associated with an encapsulated DMT-harmala alkaloid combination: results of a phase 1 study.
- Authors
- Perkins D, Halman A, Urokohara A, et al.
- Journal
- Scientific reports, 2025
- Molecules
- DMT, Ayahuasca
- Conditions
- Healthy volunteers
- Participants
- 9
- Evidence grade
- Very low
- Source
- Read the original paper
The question
What kind of acute psychedelic experience does a capsule containing DMT plus harmala alkaloids produce, and are those experiences linked to lasting psychological changes?
What they did
Researchers gave purified and partially purified plant-derived capsules containing set amounts of DMT and three harmala alkaloids (the compounds that make oral DMT active, as in ayahuasca) to 9 healthy volunteers across 17 dosing sessions. Participants filled out three questionnaires about the acute experience: the MEQ-30 (mystical-type experience), the 5D-ASC (altered states of consciousness) and a newly adapted measure called the SIME. The team used correlations and statistical models to look at dose-response patterns and links with reported lasting psychological effects, and compared scores with those reported by ayahuasca drinkers in naturalistic settings.
What they found
Total dose showed strong, statistically significant positive correlations with MEQ and SIME scores, meaning higher doses went with more intense mystical-type and related experiences. The purified DMT-harmala formulation reliably produced strong acute subjective experiences, with scores higher than those reported in most previous studies. Those experiences were associated with a range of self-reported beneficial persisting psychological effects. The authors concluded the formulation merits testing in controlled clinical trials with patient groups.
The fine print
Only 9 healthy volunteers took part, across 17 sessions, so findings are preliminary and may not generalize. There was no placebo or control condition and no blinding described, and outcomes were self-reported questionnaires rather than clinical measures of illness. Comparisons with ayahuasca drinkers came from other studies, not a head-to-head test, and associations between experience intensity and later effects do not prove cause. This summary is based on the abstract only.
What it means
An early-stage study suggests a standardized DMT-harmala capsule can reliably produce intense psychedelic experiences that participants linked to positive after-effects, but it was far too small and uncontrolled to say anything about treating any condition.
Evidence grade: Very low. A very small phase 1 study in 9 healthy volunteers with no control group or placebo comparison, relying on self-reported questionnaires.
This summary is based on the study’s published abstract.