DMT

Dose-response study of N,N-dimethyltryptamine in humans. I. Neuroendocrine, autonomic, and cardiovascular effects

This study (1994) was one of the first sanctioned studies using psychedelics following their classification as Schedule I substances. Participants received intravenous doses of DMT at 0.05,0.1,0.2, and 0.4 mg/kg. Neuroendocrine, autonomic, and cardiovascular effects were assessed. It was found that DMT can be safely administered to experienced hallucinogen users.

Authors

  • Rick Strassman

Published

JAMA Psychiatry
individual Study

Abstract

Background

To begin applying basic neuropharmacological hypotheses of hallucinogenic drug actions to humans, we generated dose-response data for intravenously administered dimethyltryptamine fumarate's (DMT) neuroendocrine, cardiovascular, autonomic, and subjective effects in a group of experienced hallucinogen users.

Methods

Dimethyltryptamine, an endogenous mammalian hallucinogen and drug of abuse, was administered intravenously at 0.05,0.1,0.2, and 0.4 mg/kg to 11 experienced hallucinogen users, in a double-blind, saline placebo-controlled, randomized design. Treatments were separated by at least 1 week.

Results

Peak DMT blood levels and subjective effects were seen within 2 minutes after drug administration, and were negligible at 30 minutes. Dimethyltryptamine dose dependently elevated blood pressure, heart rate, pupil diameter, and rectal temperature, in addition to elevating blood concentrations of β-endorphin, corticotropin, cortisol, and prolactin. Growth hormone blood levels rose equally in response to all doses of DMT, and melatonin levels were unaffected. Threshold doses for significant effects relative to placebo were also hallucinogenic (0.2 mg/kg and higher). Subjects with five or more exposures to 3,4-methylenedioxymethamphetamine demonstrated less robust pupil diameter effects than those with two or fewer exposures.

Conclusions

Dimethyltryptamine can be administered safely to experienced hallucinogen users and dose-response data generated for several measures hypothesized under serotonergic modulatory control. Additional studies characterizing the specific mechanisms mediating DMT's biological effects may prove useful in psychopharmacological investigations of drug-induced and endogenous alterations in brain function.

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Research Summary of 'Dose-response study of N,N-dimethyltryptamine in humans. I. Neuroendocrine, autonomic, and cardiovascular effects'

Introduction

Earlier human and animal research on classical hallucinogens (for example LSD, psilocybin, mescaline) implicated serotonergic mechanisms but varied widely in subject selection, administration methods, and outcome measurement. N,N-dimethyltryptamine (DMT) is an indole hallucinogen found in plants and animals and is notable for its very rapid onset and short duration. Because existing human data were limited and heterogeneous, the investigators sought a more systematic characterisation of DMT's subjective effects, linked to dose, in a cohort of experienced hallucinogen users. Strassman and colleagues aimed to map the psychological effects of graded intravenous DMT doses and to pilot a new instrument, the Hallucinogen Rating Scale (HRS), developed from interviews with experienced DMT users. The study therefore set out to (1) describe dose-related subjective phenomena across clinically derived symptom clusters, and (2) evaluate whether the HRS and statistical clustering or factor analysis could quantify and distinguish dose effects for future psychopharmacological comparison studies.

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Study Details

  • Study Type
    individual
  • Journal
  • Compound
  • Author
  • APA Citation

    Strassman, R. J. (1994). Dose-response study of N,N-dimethyltryptamine in humans. I. Neuroendocrine, autonomic, and cardiovascular effects. Archives of General Psychiatry, 51(2), 85. https://doi.org/10.1001/archpsyc.1994.03950020009001

References (2)

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