Risk assessment of ritual use of oral dimethyltryptamine (DMT) and harmala alkaloids.
Abstract
AIM: To extend previous reviews by assessing the acute systemic toxicity and psychological hazards of a dimethyltryptamine and beta-carboline brew (ayahuasca/hoasca) used in religious ceremonies. METHOD: A systematic literature search, supplemented by interviews with ceremony participants. RESULTS: No laboratory animal models were located that tested the acute toxicity or the abuse potential of ayahuasca. Separate animal studies of the median lethal dose of dimethyltryptamine (DMT) and of several harmala alkaloids indicated that a lethal dose of these substances in humans is probably greater than 20 times the typical ceremonial dose. Adverse health effects may occur from casual use of ayahuasca, particularly when serotonergic substances are used in conjunction. DMT is capable of inducing aversive psychological reactions or transient psychotic episodes that resolve spontaneously in a few hours. There was no evidence that ayahuasca has substantial or persistent abuse potential. Long-term psychological benefits have been documented when ayahuasca is used in a well-established social context. CONCLUSION: A decoction of DMT and harmala alkaloids used in religious ceremonies has a safety margin comparable to codeine, mescaline or methadone. The dependence potential of oral DMT and the risk of sustained psychological disturbance are minimal.
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Cardiovascular or endocrine problems, abnormal lipid metabolism, glaucoma, fever, and pregnancy are contraindications for ayahuasca consumption.
“Furthermore, cardiovascular or endocrine problems, abnormal lipid metabolism, glaucoma, fever, and pregnancy are contraindications for ayahuasca consumption (Gable, 2007).”
From The therapeutic potentials of Ayahuasca: possible effects against various diseases of civilization (2016) · cites this paper as Gable, 2007
Based on animal research, Gable's model calculation determined the median lethal dose of DMT for oral ingestion in humans to be 8 mg/kg.
“Based on animal research Gable (Gable, 2007) developed a model calculation that determined the median lethal dose of DMT in 8 mg/kg for oral ingestion in human subjects.”
From The therapeutic potentials of Ayahuasca: possible effects against various diseases of civilization (2016) · cites this paper as Gable, 2007
The average ceremonial dose of DMT in ayahuasca preparations is about 27 mg, giving ayahuasca a safety margin of approximately 20.
“The average ceremonial dose of DMT in ayahuasca preparations is about 27 mg; therefore, the safety margin for ayahuasca is approximately 20 (Gable, 2007).”
From The therapeutic potentials of Ayahuasca: possible effects against various diseases of civilization (2016) · cites this paper as Gable, 2007
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- Authors
- Gable, R. S.
- Affiliations
- Claremont Graduate University (US)
- Corresponding author
- Gable, Robert S.
- Venue
- Addiction
- Publisher
- Wiley
- Published
- 2006-12-20
- Volume
- 102
- Issue
- 1
- Pages
- 24-34
- ISSN
- 0965-2140 (ISSN-L)
- 1360-0443
- OpenAlex
- W2156120803
- Cited by
- 244
- References
- 63
- Citations by year
- 2026: 9 · 2025: 12 · 2024: 14 · 2023: 13 · 2022: 13 · 2021: 11 · 2020: 40 · 2019: 7 · 2018: 14 · 2017: 15 · 2016: 13 · 2015: 15 · 2014: 17 · 2013: 10 · 2012: 12
- FWCI
- 0.56
- Type
- journal article
- Language
- en
- Open access
- closed
- Locations
- Addiction (publishedVersion)
- PubMed (publishedVersion)
- Topics
- Social Sciences › Psychology › Clinical Psychology › Psychedelics and Drug Studies
- Life Sciences › Pharmacology, Toxicology and Pharmaceutics › Pharmacology › Alkaloids: synthesis and pharmacology
- Life Sciences › Pharmacology, Toxicology and Pharmaceutics › Toxicology › Forensic Toxicology and Drug Analysis
- Keywords
- dimethyltryptamine, harmala alkaloids, ayahuasca, ritual drug use, religious ceremonies, acute toxicity, median lethal dose, abuse liability, psychological harm, safety margin
- MeSH terms
- Alkaloids, Ceremonial Behavior, N,N-Dimethyltryptamine, Female, Heart Diseases, Humans, Male, Risk Factors, Substance-Related Disorders, Banisteriopsis
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