Effects of vaporized cannabis and alcohol on impairment

The Impact of Vaporized Cannabis Administration and Co-Administration of Alcohol on Impairment

Phase 1 Interventional Johns Hopkins University · NCT06293040

This study is testing how using alcohol and vaporized cannabis together affects people's ability to think and act, to help understand the risks of mixing these substances.

Quick facts

PhasePhase 1
Study typeInterventional
Enrollment90 (estimated)
Ages21 Years and up
SexAll
SponsorJohns Hopkins University Academic / other
Locations1 site (Baltimore, Maryland)
Trial IDNCT06293040 on ClinicalTrials.gov

What this trial studies

This human laboratory study aims to characterize the impairment associated with the co-use of alcohol and vaporized cannabis. A total of 32 participants will undergo 7 double-blind, double-dummy outpatient sessions where they will self-administer either placebo or active vaporized cannabis at varying THC doses alongside either a placebo or alcohol drink designed to achieve a specific breath alcohol concentration. The study will also include a positive control session to assess impairment at a legal driving limit. Various cognitive, behavioral, and subjective measures will be collected throughout the sessions to evaluate the effects of these substances on impairment.

Who should consider this trial

Good fit: Ideal candidates are healthy adults aged 21 and older who have a history of binge drinking and cannabis use.

Not a fit: Patients who do not consume alcohol or cannabis or who are not in good general health may not benefit from this study.

Why it matters

Potential benefit: If successful, this study could provide valuable insights into the combined effects of cannabis and alcohol, potentially informing guidelines for safe consumption and driving.

How similar studies have performed: While there have been studies on the effects of cannabis and alcohol separately, this specific combination approach is relatively novel and has not been extensively tested.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

1. Have provided written informed consent
2. Be at least 21 years of age
3. Be in good general health based on a physical examination, medical history, vital signs, and screening urine and blood tests
4. Not be pregnant or nursing (if female). All females must have a negative serum pregnancy test at the screening visit and a negative urine pregnancy test at each study visit
5. Have not donated blood in the prior 30 days
6. Report at least 1 day of binge drinking in the past 3 months (greater than 4 or 5 drinks on a single occasion for women and men, respectively)
7. Report at least 1 use of cannabis in the past 3 years
8. Provide negative urine test for illicit drug use (excluding THC) and negative breath alcohol test (0% BAC) at screening and before study sessions
9. Report at least 1 lifetime instance of simultaneous alcohol and cannabis use
10. Current concomitant prescription medication use that may interact with the investigational study drug, including inhibitors and inducers of CYP2CP and CYP3A4 as well as highly-protein bound drugs and drugs with a narrow therapeutic index such as warfarin, cyclosporine, and amphotericin B

Exclusion Criteria:

1. Psychoactive drug use (aside from cannabis, nicotine, alcohol, or caffeine) in the past month
2. History of or current evidence of significant medical condition that would put the participant at risk
3. Evidence of current psychiatric condition (MINI for DSM-V)
4. Meet criteria for severe alcohol use disorder (MINI for DSM-V)
5. CIWA-Ar score \> 9
6. Use of cannabis, on average, more than 3 days/week over past 3 months
7. Enrollment in another clinical trial or receiving of any drug as part of research within past 30 days
8. Shipley vocabulary score \<18 (corresponds to 5th grade reading level)

Where this trial is running

Baltimore, Maryland

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
Conditions Cannabis IntoxicationAlcohol Intoxication
Last reviewed 2026-06-13 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.