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.
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.
bioRxiv (Cold Spring Harbor Laboratory)
December 9, 2025
Maria Niedernhuber, Dila Suay, Michael J. Mueller et al.
1 citation
Classic serotonergic psychedelics strongly alter conscious awareness, but how they change the temporal structure of brain activity has been unclear. In a double-blind, placebo-controlled study with 25 participants using high-density EEG, an ayahuasca-inspired formulation (intranasal N,N-DMT and buccal harmine) accelerated neural dynamics: microstate duration decreased and state transitions became more frequent. Surprisingly, the sequence of microstates became less random, showing higher first-order Markov structure. This restructuring involved reduced transitions into one state (M2) and increased prevalence and accessibility of two others (M3 and M5). The psychedelic state thus produces a syntactically reconfigured, highly metastable neural dynamic, not mere randomization.
Psychopharmacology
July 14, 2026
Helena D Aicher, Joëlle Dornbierer, Luzia Caflisch et al.
A combination of harmine and DMT, the active ingredients in ayahuasca, reduces feelings of embarrassment and shame in healthy men. In a randomized trial with 28 participants, those who received the combination reported significantly less embarrassment when listening to recordings of their own singing compared to those who received a placebo. The treatment also lowered overall shame scores. Harmine alone did not produce these effects. The findings suggest that this compound may help treat psychiatric disorders where negative self-focused emotions play a key role.
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.