Acute Dose-dependent Effects of DMT-bolus Applications in Healthy Subjects (DMT BDR-Study) (DMT BDR)

Acute Dose-dependent Effects of DMT-bolus Applications in Healthy Subjects: A Placebo-controlled Cross-over Study (DMT BDR-Study).

N,N-dimethyltryptamine (DMT) is a psychoactive substance with similar effects such as LSD or psilocybin. However, DMT is less well characterized than the latter substances. The present study is a modern randomized cross-over trial, investigating different intravenous DMT boluses over a broad dose range. Thus, different doses will be tested and related to subjective and autonomic effects.

Study Overview

• Status: Completed
• Conditions: Healthy
• Intervention / Treatment: Drug: N,N-Dimethyltryptamine (5mg); Drug: N,N-Dimethyltryptamine (10mg); Drug: N,N-Dimethyltryptamine (15mg); Drug: N,N-Dimethyltryptamine (20mg); Drug: Placebo (saline); Drug: N,N-Dimethyltryptamine (25mg)

Detailed Description

N,N-dimethyltryptamine (DMT) is a naturally-occurring psychedelic substance widely used in recreational and spiritual settings (Ayahuasca). DMT is considered 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). However, to date no clinical study has investigated dose-response effects over a broad range of different doses of DMT within the same patient. The aim of the present study is to experimentally test different intravenous DMT bolus doses over a broad dose range and investigate the related subjective and autonomic effects in order to establish a precise dose-response relationship of DMT in healthy subjects.

• Study Type: Interventional
• Enrollment (Actual): 36
• Phase: Phase 1

Contacts and Locations

Study Locations

• Switzerland
  • Basel, Switzerland, 4056
    • Clinical Pharmacology & Toxicology, University Hospital Basel

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 25 years to 65 years (Adult, Older Adult)
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

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

Exclusion Criteria:

1. Chronic or acute medical condition
2. Current or previous major psychiatric disorder (e.g. psychotic disorders, mania / hypomania, anxiety disorders).
3. Psychotic disorder or bipolar disorder in first-degree relatives
4. Hypertension (SBP>140/90 mmHg) or hypotension (SBP<85 mmHg)
5. Hallucinogenic substance use (not including cannabis) more than 20 times or any time within the previous two months
6. Pregnancy or current breastfeeding
7. Participation in another clinical trial (currently or within the last 30 days)
8. Use of medication that may interfere with the effects of the study medication
9. Tobacco smoking (>10 cigarettes/day)
10. 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: Triple

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Randomized; Subjects will be administered intravenous DMT in 4 different bolus doses or placebo in randomized, counter-balanced order. The bolus applications will be separated by one hour.	Drug: N,N-Dimethyltryptamine (5mg); Intravenous bolus application over 45 seconds; Drug: N,N-Dimethyltryptamine (10mg); Intravenous bolus application over 45 seconds; Drug: N,N-Dimethyltryptamine (15mg); Intravenous bolus application over 45 seconds; Drug: N,N-Dimethyltryptamine (20mg); Intravenous bolus application over 45 seconds; Drug: Placebo (saline); Intravenous bolus application over 45 seconds
Experimental: Dose ecalation; Subjects will be administered a placebo and a maximum of 5 DMT bolus doses in an escalating dose order. The bolus applications will be separated by one hour.	Drug: N,N-Dimethyltryptamine (5mg); Intravenous bolus application over 45 seconds; Drug: N,N-Dimethyltryptamine (10mg); Intravenous bolus application over 45 seconds; Drug: N,N-Dimethyltryptamine (15mg); Intravenous bolus application over 45 seconds; Drug: N,N-Dimethyltryptamine (20mg); Intravenous bolus application over 45 seconds; Drug: Placebo (saline); Intravenous bolus application over 45 seconds; Drug: N,N-Dimethyltryptamine (25mg); Intravenous bolus application over 45 seconds

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Altered states of consciousness profile (OAV)	Altered states of consciousness profile (OAV) consisting of 42 items to be rated on a visual analog scale (0-100 mm), with higher values indicating stronger effects with higher scores representing more intense effects	Repeatedly 1 hour after each bolus application
Subjective effect ratings over time	Participants will be asked by the investigator to repeatedly rate their subjective effects verbally on a Likert scale from 0 to 10 for: "any drug effect", "good drug effect", "bad drug effect", and "fear". Ratings will be performed before and repeatedly after substance administration and will take approximately 30 sec complete.	Repeatedly 1 hour after each bolus application

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Saarbrücker Personality Questionnaire (SPF)	The SPF defines empathy as the "reactions of one individual to the observed experiences of another." It assesses 28- items on a 5-point Likert scale ranging from "Does not describe me well" to "Describes me very well". The measure has 4 subscales (Perspective Taking, Fantasy, Empathic Concern, Personal Distress) each made up of 7 different items.	Baseline
Elliot Humility Scale (EHS)	The Elliot Humility Scale (EHS) is a validated 13-item self-rating measure assessing four subscales, i.e. openness, self-forgetfulness, accurate self-assessment, and focus on others on a 5-point Likert scale ranging from "strongly disagree" to "strongly agree"	Baseline
Psychedelic experience questionnnaire (PEQ)	Assesses 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").	Repeatedly 1 hour after each bolus application
Near death experience content scale (NDE-C)	The Near-Death Experience Content (NDE-C) scale is a tool to assess dimensions of near-death experience on a Likert scale ranging from 0 ("not at all") to 4 ("extremely").	Repeatedly 1 hour after each bolus application
Spiritual Realms Questionnaire (SRQ)	Assesses the spiritual phenomenons elicited by psychedelic substances through 11 main questions to be answered on a total of 65 sub-ordered 100mm visual analog scales once on each study day	Once at the end of study day
Blood pressure	Assessed multiple times on each study day via systolic and diastolic blood pressure	Repeatedly in short intervals (2-10 minutes) after each bolus application
Heart rate	Assessed multiple times on each study day.	Repeatedly in short intervals (2-10 minutes) after each bolus application
Plasma level DMT	Assessed multiple times on each study day.	Repeatedly in short intervals (2-10 minutes) after each bolus application
Urine recovery of DMT	Assessed once on each study day	Once at the end of study day
NEO-Five-Factor-Inventory (NEO-FFI)	The NEO-FFI is a self-description questionnaire with 60 items for the measurement of the "big five": neuroticism, extraversion, openness, agreeableness, and consciousness. It uses a 5-point Likert scale ranging from "completely disagree" to "fully agree.	Baseline

Collaborators and Investigators

• Sponsor: University Hospital, Basel, Switzerland

Study record dates

Study Major Dates

• Study Start (Actual): June 12, 2024
• Primary Completion (Actual): February 2, 2025
• Study Completion (Actual): March 4, 2025

Study Registration Dates

• First Submitted: November 14, 2022
• First Submitted That Met QC Criteria: January 23, 2023
• First Posted (Actual): January 25, 2023

Study Record Updates

• Last Update Posted (Actual): April 11, 2025
• Last Update Submitted That Met QC Criteria: April 10, 2025
• Last Verified: April 1, 2025

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Physiological Effects of Drugs; Molecular Mechanisms of Pharmacological Action; Neurotransmitter Agents; Psychotropic Drugs; Serotonin Antagonists; Serotonin Agents; Hallucinogens; Serotonin Receptor Agonists; N,N-Dimethyltryptamine
• Other Study ID Numbers: BASEC 2022-01224

Drug and device information, study documents

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