Frontiers in psychiatry
January 1, 2023
Helena D Aicher, Michael J Mueller, Dario A Dornbierer et al.
34 citations
A standardized formulation combining the monoamine oxidase inhibitor harmine (100 mg orodispersible tablet) with incremental intranasal N,N-dimethyltryptamine (DMT, up to 100 mg) produced a psychedelic experience in 31 healthy male subjects, as measured by the 5D-ASC rating scale. The experience was characterized by psychological insights, emotional breakthroughs, and low scores on challenging experiences. Participants reported personal and spiritual significance and mainly positive persisting effects at 1- and 4-month follow-ups. No changes in trait personality, psychological flexibility, general well-being, or increases in psychopathology were observed. The formulation appears well tolerated and may support psychotherapy, but further studies in patients are needed.
Frontiers in pharmacology
January 1, 2023
Dario A Dornbierer, Laurenz Marten, Jovin Mueller et al.
32 citations
Ayahuasca, an Amazonian plant medicine containing DMT and harmine, shows promise for mental health disorders but its oral use causes gastrointestinal side effects and unpredictable drug levels. This study tested new ayahuasca-analogue formulations in 10 healthy men: an oral capsule of purified DMT and harmine versus a combined oromucosal harmine tablet with intranasal DMT spray. The combined buccal/intranasal route significantly reduced variations in systemic exposure and attenuated common side effects like nausea, vomiting, and diarrhea compared to traditional oral ayahuasca. All preparations were well tolerated. This approach may enable safer, patient-friendly DMT/harmine administration for affective disorders.
Biomedicine & pharmacotherapy = Biomedecine & pharmacotherapie
March 1, 2025
Klemens Egger, Javier Jareño Redondo, Jovin Müller et al.
14 citations
Ayahuasca contains DMT and harmine, but their interactions are not fully understood. In a single-blind, randomized, two-arm, factorial dose-finding study with 16 healthy participants, each received six dose combinations of DMT (0-120 mg) and harmine (0-180 mg) via a transmucosal delivery system. All combinations produced dose-dependent subjective effects lasting 4-5 hours, with peak DMT and harmine levels reaching 33 ng/mL and 49 ng/mL, respectively. The interaction was bidirectional: harmine reduced DMT metabolism, while DMT altered harmine pharmacokinetics. The formulation had a favorable safety profile, supporting further testing for affective disorders.
The international journal of neuropsychopharmacology
December 28, 2024
Michael J Mueller, Helena D Aicher, Dario A Dornbierer et al.
10 citations
A new pharmaceutical formulation combining pure DMT and harmine produced ayahuasca-like psychological effects lasting 2-3 hours in 31 healthy male volunteers, with consistent drug levels and no serious adverse events. DMT reached peak plasma concentrations of 22.1 ng/mL, while buccal harmine reached 32.5 ng/mL in a sustained-release profile but caused no distinguishable subjective effects on its own. All drug conditions were safe and well tolerated, suggesting the formulation could reduce risks and improve therapeutic outcomes for mental health disorders.
NeuroImage
June 1, 2025
Dila Suay, Helena D Aicher, Micheal Kometer et al.
4 citations
A psychedelic formulation combining DMT and harmine, inspired by ayahuasca, altered brain responses to faces in 30 healthy men. It increased early visual reactivity (P1 wave) and disrupted face-structural encoding (N170 wave) for all face types. Crucially, it reduced the neural distinction between self and other faces in the P300 wave, while familiar-face processing remained stable. Harmine alone did not produce these effects. The findings suggest psychedelics can reorganize self-related neural dynamics, potentially promoting cognitive flexibility and offering therapeutic benefits for conditions involving rigid self-focus, such as depression and social anxiety.
Biomedicine & pharmacotherapy = Biomedecine & pharmacotherapie
July 9, 2025
Angela Äbelö, John W Smallridge, Robin von Rotz et al.
3 citations
The psychedelic compound DMT is often taken with harmine, a monoamine oxidase inhibitor, as in ayahuasca, but how harmine alters DMT's effects was not well understood. In a study of 16 healthy adults, six combinations of buccal DMT (0-120 mg) and harmine (0-180 mg) were given. Harmine increased DMT's bioavailability and prolonged its absorption, leading to higher and more sustained blood levels. The intensity of subjective psychedelic effects rose with dose, and harmine potentiated these effects at higher DMT doses. A mathematical model captured these relationships and individual variability, offering a foundation for more personalized dosing in psychedelic therapy.
Journal of psychopharmacology (Oxford, England)
June 19, 2025
Helena D Aicher, Ilhui A Wicki, Daniel Meling et al.
2 citations
A single dose of an ayahuasca-inspired DMT/harmine formulation increased mindfulness and compassion in 31 healthy participants one day after administration. The randomized, double-blind, placebo-controlled trial found significant effects on mindfulness, self-compassion, and compassion with others, with larger effects in participants who reported higher sensitivity to the drug. These results suggest the formulation may have therapeutic potential for enhancing traits relevant to mood disorders, though further research in clinical settings is needed.
Journal of psychopharmacology (Oxford, England)
August 16, 2025
Dila Suay, Helena D Aicher, Berit Singer et al.
A psychedelic formulation combining DMT and harmine, but not harmine alone, impaired convergent thinking—the ability to find a single correct solution—in 30 healthy men, especially those with higher baseline reasoning. Divergent thinking, the generation of many ideas, showed no overall effect but trended toward reduced fluency and elaboration. In a real-world painting task, both DMT/HAR and harmine reduced transitions associated with incubation, and DMT/HAR uniquely decreased the shift from incubation to illumination, indicating altered pathways to insight. Subjective experiences like altered meaning and insightfulness predicted divergent but not convergent thinking. The effects of DMT/HAR on creativity are not uniform, affecting both cognitive performance and the dynamic creative process.