Neural Effects of Intravenous N,N-dimethyltryptamine (DMT)

NCT07693257 | Not Yet Recruiting Phase 1 FDA Drug

• 1 other identifier: 812478
• Study Type: interventional
• Target: 20
• Locations: 1 country
• Sites: 1

Brief Summary

This study examines how the psychedelic substance DMT affects the human brain when administered by the intravenous (IV) route. DMT is a naturally occurring chemical in the body that is thought to help improve mood when ingested in a continuously monitored medical setting. Previous research has shown that a single IV injection of DMT can be given safely, but its effects, which include changes in perception, emotions, and thinking, usually wear off within 15-20 minutes. To better understand what happens when DMT's effects last longer, researchers have developed a method to give DMT slowly and continuously through an IV, which safely extends its effects for up to an hour or more. In this study, healthy volunteers who have prior experience using DMT will receive low and medium doses of DMT in this extended manner through an IV for 1 hour while undergoing a brain scanning technique known as functional magnetic resonance imaging (fMRI). These scans allow researchers to see changes in brain activity and blood flow in real time. Participants will complete psychological assessments before and after receiving DMT, and additional brain scans without DMT will be used for comparison. The researchers will also use advanced computer techniques to help identify brain patterns linked to the visual experiences people report during DMT. Overall, the goal of the study is to better understand how DMT affects the brain during an extended experience and to learn more about the biological processes behind its psychological effects.

Conditions

Healthy Participants Study

Keywords

Intravenous DMT; DMT; Healthy; fMRI; Psychedelics; N,N-dimethyltryptamine

Outcome Measures

Primary Outcomes (1)

• fMRI - Blood Oxygen Level Dependent (BOLD) Signaling

  Whole brain BOLD fMRI acquired during the peak subjective effects of IV administration of two separate doses ("low" and "medium") of DMT hemifumarate over a 60 min period for comparison across time, between dose, and versus rest/saline infusion.

  Up to 3 months: Assessed at baseline fMRI (Visit 2) and dosing fMRI (Visits 6, 8).

Secondary Outcomes (20)

• Numeric Rating Sale for current anxiety and pain, and feelings of compassion toward oneself and other

  Up to 4 months: Assessed at baseline fMRI (Visit 2), dosing fMRI (Visits 6, 8), integration (Visits 7, 9), and follow-up (Visits 10, 11, 12)

• Numeric Rating Sale for current mood and stress

  Up to 6 months: Assessed at baseline (Visit 2), dosing fMRI (Visits 6, 8), integration (Visits 7, 9), follow-up (Visits 10, 11, 12), and post-dosing fMRI (Visits 13, 14, 15)

• Numeric Rating Scale for immersion, visual effects, distortion in time perception, good and bad drug effects, drug intensity, and entity phenomena experienced

  Up to 3 months: Assessed at baseline fMRI (Visit 2), and dosing fMRI (Visits 6, 8)

• Hallucinogen Rating Scale

  Up to 3 months: Assessed at baseline fMRI (Visit 2), and dosing fMRI (Visits 6, 8)

• Autonomous Entity Questionnaire

  Up to 3 months: Assessed at baseline fMRI (Visit 2), and dosing fMRI (Visits 6, 8)

Other Outcomes (5)

• Participant validation of BOLD fMRI-based visual decoding models

  Up to 6 months: Assessed at dosing fMRI (Visits 6, 8) post-dosing fMRI (Visits 13, 14, 15), and validation (Visit 16)

• Plasma levels of DMT, indole-3-acetic acid, and DMT-N-Oxide

  110 minutes

• Salivary levels of DMT, indole-3-acetic acid, and DMT-N-Oxide

  60 minutes

Study Arms (2)

DMT hemifumarate "low" dose

EXPERIMENTAL

Participants will be randomized to receive, in a double-blinded, counter-balanced, and crossover design, two doses of IV DMT during fMRI scanning delivered within two weeks apart under the care of a study physician.

Drug: N,N-Dimethyltryptamine (15 mg)

DMT hemifumarate "medium" dose

EXPERIMENTAL

Participants will be randomized to receive, in a double-blinded, counter-balanced, and crossover design, two doses of IV DMT during fMRI scanning delivered within two weeks apart under the care of a study physician.

Drug: N,N-Dimethyltryptamine (17.5 mg)

Interventions

N,N-Dimethyltryptamine (15 mg) DRUG

Participants will receive one "low" dose (15 mg for 1 min + 1.5 mg/min for 59 min) of synthetic DMT (hemifumarate) via IV injection.

DMT hemifumarate "low" dose

N,N-Dimethyltryptamine (17.5 mg) DRUG

Participants will receive one "medium" dose (17.5 mg for 1 min + 1.75 mg/min for 59 min) of synthetic DMT (hemifumarate) via IV injection.

DMT hemifumarate "medium" dose

Eligibility Criteria

• Age: 18 Years - 65 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• to 65 years of age
• Able to fluently communicate in English
• Agree to sign the consent and HIPAA authorization
• Not taking serotonergic antidepressant medication
• Willing to refrain from using any non-prescribed psychoactive drugs, including alcohol, within 24 hours before and after study drug administration
• Willing to refrain from consumption of illicit psychoactive substances during the study
• Agree not to use any nonprescription medications, herbal medications, or supplements during the week prior to each drug session unless an exception is approved by the study investigators
• Willing to refrain from smoking or use of nicotine from 8:00 AM on the morning of drug sessions until discharge at the end of the session
• Have used classic serotonergic hallucinogens (e.g., LSD, psilocybin mushrooms, ayahuasca) without untoward/adverse effects and report "liking" psychedelic drugs with no previous adverse reactions to DMT or other psychedelics
• Report at least 20 lifetime uses of psychedelics, including at least 5 uses of DMT (any form), at least one via inhalation, at least once within the past 2 years, and not within the past 3 months
• Able to remain in an fMRI scanner without sedation and pass fMRI safety screening
• Refrain from caffeine use prior to fMRI scanning
• Women of childbearing potential must agree to use effective birth control from screening through the final visit
• Have a relative or friend available to provide transportation after the drug session
• Not taking medications acting as serotonin antagonists (e.g., cyclobenzaprine, ondansetron), dopamine antagonists (e.g., metoclopramide, promethazine, prochlorperazine), dopamine agonists (e.g., levodopa, pramipexole, apomorphine), psychostimulants (e.g., modafinil, armodafinil, solriamfetol, methylphenidate, dexmethylphenidate, atomoxetine, dextroamphetamine, mixed amphetamine salts, lisdexamfetamine), anticholinergics (e.g., benztropine, trihexyphenidyl, scopolamine, hyoscyamine), or NMDA receptor antagonists (e.g., amantadine, memantine, ketamine)

You may not qualify if:

• Pregnant or nursing females
• Females of childbearing potential who are sexually active but not using birth control
• MRI contraindications (e.g., pacemakers, metal implants, spinal cord stimulators)
• Current DSM-5 diagnosis of depression or anxiety (or within past 6 months), bipolar disorder, schizophrenia, or other psychotic disorder
• First-degree relative with bipolar disorder, schizophrenia, or other psychotic disorder
• Suicide risk as determined by clinician assessment and/or C-SSRS
• Active substance use disorder (excluding tobacco and caffeine)
• Use of serotonergic dietary supplements (e.g., 5-hydroxytryptophan, St. John's wort, SAM-e) if unwilling to discontinue for study duration
• Neurological conditions affecting cognition or perception (e.g., dementia, traumatic brain injury, mild cognitive impairment)
• Positive urine drug screen for amphetamines, barbiturates, buprenorphine, cocaine, methamphetamine, MDMA, methadone, opiates, or phencyclidine
• Use of DMT or another serotonergic hallucinogen within the past 3 months
• Concomitant treatment with antipsychotic medications
• Concomitant treatment with antidepressants, MAO inhibitors, or serotonin reuptake inhibitors (trazodone ≤50 mg/day for insomnia allowed but not within 48 hours of DMT session)
• Severe hearing or visual impairment
• History of seizure disorder or epilepsy

Sponsors & Collaborators

• Jon Dean: lead

Study Sites (1)

Altman Clinical and Translational Research Institute

La Jolla, California, 92037, United States

Location

MeSH Terms

Interventions

N,N-Dimethyltryptamine

Intervention Hierarchy (Ancestors)

Tryptamines; Biogenic Monoamines; Biogenic Amines; Amines; Organic Chemicals; Indoles; Heterocyclic Compounds, 2-Ring; Heterocyclic Compounds, Fused-Ring; Heterocyclic Compounds

Study Officials

• Jon Dean, PhD

  UCSD

  PRINCIPAL INVESTIGATOR

Central Study Contacts

Yasmeen Esshaki

CONTACT

619-786-0375; deanlaboratory@health.ucsd.edu

Study Design

• Study Type: interventional
• Phase: phase 1
• Allocation: RANDOMIZED
• Masking: DOUBLE
• Who Masked: PARTICIPANT, INVESTIGATOR
• Purpose: BASIC SCIENCE
• Intervention Model: CROSSOVER
• Sponsor Type: OTHER
• Responsible Party: SPONSOR INVESTIGATOR
• PI Title: Assistant Professor, Director of DMT Research

Study Record Dates

• First Submitted: February 6, 2026
• First Posted: July 9, 2026
• Study Start (Estimated): September 1, 2026
• Primary Completion (Estimated): September 1, 2028
• Study Completion (Estimated): September 1, 2029
• Last Updated: July 9, 2026

Record last verified: 2026-07

Locations

US (1)