An interventional study of Alcohol beverage and Cannabis (smoked flower) in Substance Use Behavior, Cannabis Intoxication and Alcohol Intoxication, sponsored by University of Colorado, Denver. Not yet recruiting at 1 site in United States. Open to participants aged 21 Years to 30 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2026-11-06.
Sponsored by University of Colorado, Denver · Not applicable, Interventional, and Basic science
The goal of this randomized clinical trial is to learn how alcohol use, cannabis use, and using both substances affect whether and how quickly people stop a video being shown to a woman. The study will recruit 312 people from the Metro-Denver area who drink alcohol and use cannabis; half of the participants will be women. The main questions it aims to answer are:
Researchers will compare four randomly assigned groups: alcohol only, cannabis only, both alcohol and cannabis, and neither substance. Participants will also be randomly assigned to one of two scenarios involving alcohol use or alcohol and cannabis use by others. These comparisons will help researchers understand how participants' own substance use and substance use by others affect their decisions to intervene.
Participants will:
76 studies on the registry are indexed under Alcoholic Intoxication; 17 are open to participants now.
This study's planned enrollment of 312 is above the median of 135 across 62 interventional studies indexed under Alcoholic Intoxication.
Browse Alcoholic Intoxication studies →University of Colorado, Denver is the lead sponsor of 1,543 studies on the registry; 317 are open to participants now.
Of its 147 completed or terminated interventional studies of FDA-regulated products, 92 (63%) have results posted.
Counted across the registry records on this site, refreshed daily.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Participants will be assigned to drink alcohol and the others in the study will also be assigned to drink alcohol.
Drug: Alcohol beverage · Other: Alcohol Consumption of Others
Participants will be assigned to drink alcohol and the others in the study will be assigned to drink alcohol and consume cannabis.
Drug: Alcohol beverage · Other: Alcohol/Cannabis Consumption of Others
Participants will be assigned to drink alcohol and consume cannabis; and the others in the study will be assigned to drink alcohol.
Drug: Simultaneous Alcohol and Cannabis · Other: Alcohol Consumption of Others
Participants will be assigned to drink alcohol and consume cannabis; and the others in the study will be assigned to drink alcohol and consume cannabis.
Drug: Simultaneous Alcohol and Cannabis · Other: Alcohol/Cannabis Consumption of Others
Participants will be assigned to drink a non-alcohol control beverage; and the others in the study will be assigned to drink alcohol.
Other: Alcohol Consumption of Others · Other: No-Alcohol/Cannabis Control
Participants will be assigned to drink a non-alcohol control beverage; and the others in the study will be assigned to drink alcohol and consume cannabis.
Other: Alcohol/Cannabis Consumption of Others · Other: No-Alcohol/Cannabis Control
Participants will be assigned to consume cannabis, and the others in the study will be assigned to drink alcohol.
Drug: Cannabis (smoked flower) · Other: Alcohol Consumption of Others
Participants will be assigned to consume cannabis, and the others in the study will be assigned to drink alcohol and consume cannabis.
Drug: Cannabis (smoked flower) · Other: Alcohol/Cannabis Consumption of Others
Participants will consume a moderate alcohol dose condition (target BrAC .08%) with the National Institute on Alcohol Abuse and Alcoholism (NIAAA) approved alcohol administration procedures.
Participants in this group will self-administer legal-market flower cannabis
Participants in this group will self-administer legal-market flower cannabis Participants will consume a moderate alcohol dose condition (target BrAC .08%) with the National Institute on Alcohol Abuse and Alcoholism (NIAAA) approved alcohol administration procedures.
Others in the study will be assigned to drink alcohol
Others in the study will be assigned to drink alcohol and consume cannabis
Participants will be assigned to a no-alcohol control beverage and to not consume cannabis.
Intervention Likelihood
Stopping a woman from watching content during the Bystander Intervention Paradigm (Parrott et al., 2012, Leone et al., 2015). Possible scores are 0 (not stopping) to 1 (stopping).
Time frame: Up to three hours after consent
Intervention Speed
The amount of time the woman watches the sexually explicit film during the Bystander Intervention Paradigm (Parrott et al., 2012, Leone et al., 2015). Scores range from 0 to 4 minutes.
Time frame: Up to three hours after consent
Number of Bystander Barriers
Count number of barriers experienced during the paradigm via a semi-structured interview.
Time frame: Up to four hours after consent
Number of Bystander Facilitators
Count number of facilitators experienced during the paradigm via a semi-structured interview.
Time frame: Up to four hours after consent
Plan to share: Yes — IPD will be available in the NIAAA Data Archive.
No publications or documents are linked to this record.
Start is estimated for May 2027; primary completion for Mar 2031, 46 months later.
Of 29 interventional studies with no phase under Alcoholic Intoxication, half reached primary completion within 40 months of starting (the median), counting those still running; a quarter within 12 and three quarters within 58. This study's planned 46 months is above that.
How these figures are worked out, and which studies are left out of them.
From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
This study is not yet recruiting, as verified in Nov 2026. You cannot join it, but the record below documents what was studied.
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Studies of the drug tested here: Cannabis sativa subsp. indica TOP
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