Effects of Dimethyltryptamine in Healthy Subjects (DMT)

Effects of Dimethyltryptamine (DMT) in Healthy Subjects: A Placebo-controlled Cross-over Study

N,N-dimethyltryptamine (DMT) is a naturally-occurring psychedelic substance widely used in recreational and spiritual settings. DMT can be used as a tool to induce an altered state of consciousness of interest in psychological and psychiatric research. DMT is rapidly metabolized by monoamine oxidase (MAO) A. Therefore, it is inactive when administered orally and has a very short duration of action when administered parenterally (<20 min).Therefore, an intravenous administration regime including a bolus and maintenance perfusion has been proposed to induce a stable and prolonged DMT experience allowing to study the psychological and autonomic acute effects of DMT. This administration allows to induce and end an altered state safely and quickly. The goal of the present study is to experimentally test different intravenous DMT administration schedules to investigate the subjective and autonomic effects of DMT in healthy subjects.

Study Overview

• Status: Completed
• Conditions: Healthy
• Intervention / Treatment: Drug: Saline; Drug: Dimethyltryptamine (DMT)

Detailed Description

N,N-dimethyltryptamine (DMT) is a naturally-occurring psychedelic substance widely used in recreational and spiritual settings in the form of Ayahuasca. Similar to lysergic acid diethylamide (LSD) or psilocybin, DMT is considered a tool to induce an altered state of consciousness of interest in psychological and psychiatric research. Pharmacologically, DMT interacts with the serotonin 5-HT2A receptor similar to other classic hallucinogens including LSD and psilocybin. The main difference of DMT in comparison with LSD or psilocybin is inactivity when administered orally without monoamine oxidase (MAO) A inhibition and its short action when administered intravenously or by inhalation. In Ayahuasca, DMT is consumed iin combination with harmala alkaloids that inhibit MAO to increase the oral bioavailability of DMT and to prolong its action after oral use. Alternatively, an intravenous administration regime including a bolus and a one hour maintenance perfusion has been proposed to induce a stable and prolonged DMT experience, allowing to study the psychological and autonomic acute effects of DMT. Also, the maintenance perfusion administration allows to end an altered state of consciousness quickly. In the present study this model will be tested using four modified administration schemes. The goal of this study is to experimentally test different intravenous DMT administration schedules to investigate the subjective and autonomic effects of DMT in healthy subjects. The study is expected to inform researchers on dosing regimes of intravenous DMT as a tool to examine alterations of the mind and is of interest for psychology and psychiatry. This study does not intend to provide any therapeutic benefit for the participants. Currently, no study has validly determined the elimination half-life of DMT and other pharmacokinetic parameters. The key aim is to test the dose-response of DMT as well as the difference between the loading dose bolus and no-bolus perfusion conditions regarding pharmacokinetic, subjective, and autonomic effects including psychological and physical tolerability.

• Study Type: Interventional
• Enrollment (Actual): 31
• Phase: Phase 1

Contacts and Locations

Study Locations

• Switzerland
  • Basel-Stadt BS
    • Basel, Basel-Stadt BS, Switzerland, 4031
      • University Hospital Basel

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 25 years to 65 years (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• Age between 25 and 65 years old
• Sufficient understanding of the German language
• Understanding of procedures and risks associated with the study
• Willing to adhere to the protocol and signing of the consent form
• Willing to refrain from the consumption of illicit psychoactive substances during the study
• Abstaining from xanthine-based liquids from the evenings prior to the study sessions and during the sessions
• Willing not to operate heavy machinery within 6 h of DMT administration
• Willing to use double-barrier birth control throughout study participation
• Body mass index between 18-29 kg/m2

Exclusion Criteria:

• Chronic or acute medical condition
• Current or previous major psychiatric disorder
• Psychotic disorder or bipolar disorder in first-degree relatives
• Hypertension (SBP>140/90 mmHg) or hypotension (SBP<85 mmHg)
• Hallucinogenic substance use (not including cannabis) more than 20 times or any time within the previous two months
• Pregnancy or current breastfeeding
• Participation in another clinical trial (currently or within the last 30 days)
• Use of medication that may interfere with the effects of the study medication
• Tobacco smoking (>10 cigarettes/day)
• Consumption of alcoholic beverages (>20 drinks/week)

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: Randomized
• Interventional Model: Crossover Assignment
• Masking: Quadruple

Number of Arms

5

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Placebo Comparator: Placebo; Bolus of 0 mg DMT + perfusion of 0 mg/min DMT over 60 min, resulting in a total dose of 0 mg DMT.	Drug: Saline; Intravenous saline bolus and/or saline maintenance perfusion over 90 min
Experimental: Low dose; Intravenous bolus of 0 mg DMT + perfusion of 0.6 mg/min DMT over 90 min, resulting in a total dose of 54 mg DMT.	Drug: Saline; Intravenous saline bolus and/or saline maintenance perfusion over 90 min; Drug: Dimethyltryptamine (DMT); Intravenous DMT bolus and/or DMT maintenance perfusion over 90 min
Experimental: Low dose with bolus; Intravenous bolus of 15 mg DMT + perfusion of 0.6 mg/min DMT over 90 min, resulting in a total dose of 69 mg DMT.	Drug: Dimethyltryptamine (DMT); Intravenous DMT bolus and/or DMT maintenance perfusion over 90 min
Experimental: High dose; Intravenous bolus of 0 mg DMT + perfusion of 1 mg/min DMT over 90 min, resulting in a total dose of 90 mg DMT.	Drug: Saline; Intravenous saline bolus and/or saline maintenance perfusion over 90 min; Drug: Dimethyltryptamine (DMT); Intravenous DMT bolus and/or DMT maintenance perfusion over 90 min
Experimental: High dose with bolus; Intravenous bolus of 25 mg DMT + perfusion of 1 mg/min DMT over 90 min, resulting in a total dose of 115 mg DMT.	Drug: Dimethyltryptamine (DMT); Intravenous DMT bolus and/or DMT maintenance perfusion over 90 min

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Altered states of consciousness profile	Assessed once on each study day via 5 Dimensions of Altered States of Consciousness (5D-ASC) scale consisting of 94 items to be rated on a visual analog scale (0-100 mm), with higher values indicating stronger effects	150 minutes
Subjective effect ratings over time	Assessed 22 times on each study day via Subjective Effect Scale (SES), consisting of 4 questions to be rated on a Likert scale ranging from 1 to 10, with higher ratings indicating stronger effects	150 minutes

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Effect moderation through personality traits I	Assessed via NEO-Five-Factor-Inventory (NEO-FFI)	Baseline
Effect moderation through personality traits II	Assessed via Freiburger Personality Inventory (FPI)	Baseline
Effect moderation through personality traits III	Assessed via Saarbrücker Personality Questionnaire (SPF)	Baseline
Subjective mood ratings	Assessed twice on each study day via the Adjective Mood Rating Scale (AMRS) consisting of 60 items to be rated on a 4-point Likert scale, with higher ratings indicating stronger identification with the specific mood	150 minutes
Mystical-type experiences	Assessed once on each study day via States of Consciousness Questionnaire (SCQ) which measures the emergence and intensity of phenomenons occurring in altered states of consciousness on a 6-point Likert scale ranging from 0 ("not at all") to 5 ("extremely")	150 minutes
Autonomic effects I	Assessed 22 times on each study day via systolic and diastolic blood pressure, Emax	150 minutes
Autonomic effects II	Assessed 22 times on each study day via heart rate, Emax	150 minutes
Plasma levels of DMT	Assessed 21 times on each study day via blood samples	150 minutes
Plasma levels of blood-derived neurotrophic factor (BDNF)	Assessed 21 times on each study day via blood samples	150 minutes
Plasma levels of oxytocin	Assessed twice on each study day via blood samples	60 minutes
Renal clearance of DMT	Collected once per study day via one-time interval urine recovery	3 hours
Effect moderation through personality trait IV	Assessed via Elliot Humility Scale (EHS) which measures the personality trait humility through 13 items on a 5-point Likert scale ranging from "strongly disagree" to "strongly agree"	Baseline
Effect moderation through personality trait V	Assessed via Jankowski Humility Scale (JHS) which measures the personality trait humility through 18 items on a 5-point Likert scale ranging from "not at all" to "strongly"	Baseline
Effect moderation through personality trait VI	Assessed via Arnett Inventory of Sensation Seeking (AISS-d)	Baseline
Effect moderation through personality trait VII	Assessed via Defense Style Questionnaire (DSQ-40)	Baseline
Adverse effects	Assessed via the List of Complaints (LC) which covers the emergence of 66 complaints in a yes/no format	150 minutes

Collaborators and Investigators

• Sponsor: University Hospital, Basel, Switzerland
• Investigators: Principal Investigator: Matthias E Liechti, Prof. Dr. MD, University Hospital, Basel, Switzerland

Study record dates

Study Major Dates

• Study Start (Actual): June 18, 2021
• Primary Completion (Actual): August 29, 2022
• Study Completion (Actual): September 22, 2022

Study Registration Dates

• First Submitted: April 6, 2020
• First Submitted That Met QC Criteria: April 15, 2020
• First Posted (Actual): April 20, 2020

Study Record Updates

• Last Update Posted (Actual): October 12, 2022
• Last Update Submitted That Met QC Criteria: October 10, 2022
• Last Verified: October 1, 2022

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Physiological Effects of Drugs; Neurotransmitter Agents; Molecular Mechanisms of Pharmacological Action; Psychotropic Drugs; Serotonin Agents; Serotonin Receptor Agonists; Serotonin Antagonists; Hallucinogens; N,N-Dimethyltryptamine
• Other Study ID Numbers: BASEC 2020-00376

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: No

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No