Substance Use Disorders (SUD)SchizophreniaAyahuasca

Risk assessment of ritual use of oral dimethyltryptamine (DMT) and harmala alkaloids

This relatively early study (2006) combined a literature review with interviews of ceremony participants to establish the effects and toxicity of ayahuasca. The author concludes that risks are relatively low (transient psychological effects, low toxicity, low abuse/addiction potential).

Authors

  • Gable, R. S.

Published

Addiction
meta Study

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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Research Summary of 'Risk assessment of ritual use of oral dimethyltryptamine (DMT) and harmala alkaloids'

Introduction

Gable frames the paper as a risk-focused review of ceremonial oral dimethyltryptamine (DMT) combined with b‑carboline monoamine oxidase inhibitors (commonly known as ayahuasca or hoasca). Earlier literature and legal debate motivated the review: a US Supreme Court case over the sacramental use of hoasca highlighted limited systematic evidence about acute systemic toxicity, psychological hazards and dependence potential. The introduction emphasises that ‘‘risk’’ is treated probabilistically and that, because published data on orally administered DMT are sparse, many alleged effects remain only plausibly associated rather than causally established. The paper sets out to assemble and evaluate available scientific and technical information on acute toxicity, cardiovascular effects, psychological adverse reactions and dependence/abuse potential of ayahuasca/hoasca. Gable takes a broad view of potential hazards, including pharmacological properties of the two principal constituents (DMT and harmala alkaloids), customary patterns of preparation and ceremonial use, and supplementary information obtained from participant observation and legal documentation, with the aim of estimating relative safety margins and identifying circumstances that increase risk.

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Study Details

References (7)

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