Alcohol Use DisorderNCT05999344
Alcohol and Cannabis Concentrates Co-Administration
A study testing commercially available cannabis administered prior to commercially available alcohol and commercially available alcohol administered prior to commercially available cannabis in people with Alcohol Use Disorder and Cannabis Use, run by University of Colorado, Denver at 1 site in United States.
Trial summary
The goal of this study is to learn about the effects of combining alcohol with cannabis concentrate products which contain high levels of THC. The main question[s] it aims to answer are, 1) How does the order in which someone consumes THC and alcohol in a given co-use session impact outcomes such as blood alcohol… Read more about this study
- Who is it for?
- Ages 21 to 65 yearsHealthy volunteers can take part
- Conditions the study is for
- Alcohol Use Disorder, Cannabis Use
- What is being tested?
- commercially available cannabis administered prior to commercially available alcohol and commercially available alcohol administered prior to commercially available cannabis
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 146 participants
- Where
- 1 siteUnited States
- Study dates
- 16 Dec 2021to 1 Aug 2024
- Phase
- Interventional
- Are there results?
- None posted in the registry
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 21 to 65 years
- All sexes
- Healthy volunteers accepted
- Adult, Older adult
Who may be able to join
- 21-65 years old,
- Heavy drinkers (for men, >4 drinks in one occasion, or >14 drinks per week; for women, >3 drinks in one occasion, or >7 drinks per week)
- Regular users of legal-market cannabis (at least 3x/week in past 3 months)
- Have experience using cannabis concentrates within the last year
- Willing to obtain a concentrate product of their choice for use in the study.
Who cannot join
- Diagnosed with or seeking treatment for alcohol use disorder (AUD) or other substance use disorder (SUD)
- Pregnant, breastfeeding or trying to become pregnant
- Meet criteria for psychotic, bipolar or major depressive disorder with suicidal ideation, or history of these disorders
- Current use of psychotropic (except anti-depressants) or steroid medications
- Report illicit drug use in past 60-days or fail drug screen (drug screen tests for the presence of amphetamines, benzodiazepines, cocaine, THC, methamphetamine and opioids; only THC is allowed to be present in urine in order to be eligible to participate in the study
- Major medical condition contraindicating alcohol and/or cannabis consumption (e.g., liver disease, heart disease, or being told by a doctor that it is unsafe to consume alcohol or cannabis due to a medical condition)
- Have participated in another research study in the past 8 weeks.
Trial locations and contacts
1 site in 1 country.
United States1 site
Colorado State University
Fort Collins, Colorado, 80523
About this study
Official title: Exploring Intoxication During Acute Alcohol and Cannabis Concentrate Co-Administration: A Focus on Cannabinoid Content and Order Effects
The goal of this study is to learn about the effects of combining alcohol with cannabis concentrate products which contain high levels of THC. The main question[s] it aims to answer are, 1) How does the order in which someone consumes THC and alcohol in a given co-use session impact outcomes such as blood alcohol level, heart rate or subjective drug effects, and 2) how does THC percentage in cannabis influence outcomes following alcohol and cannabis co-administration. Participants will be scheduled for our mobile lab to come to their residence. During the session, they will:
- consume a standardized dose of alcohol as well as use their own preferred cannabis concentrate product.
- they will then remain in our mobile lab for about 4 hours and complete some surveys as well as do some cognitive tasks on an iPad every 30 minutes.
- They will also have their blood drawn three times throughout the session, and will periodically be asked to blood into a breathalyzer to measure blood alcohol level.
Researchers will compare people who use alcohol prior to cannabis to those who use cannabis prior to alcohol to determine whether order of use impacts outcomes.
Read the detailed description
Individuals who drink alcohol commonly report co-using cannabis, and the increasing availability of new formulations of highly potent cannabis products on the legal market means that alcohol is likely being combined with cannabis products that contain high levels of delta-9-tetrahydrocannabinol (THC). There is limited existing research on the acute effects of cannabis products containing high amounts of THC, such as cannabis concentrates, which often contain up to 90% THC. Existing laboratory data suggests that consuming alcohol and cannabis together (compared to alcohol alone) is associated with reduced BAC, delayed time to peak blood alcohol concentration (BAC), longer duration of intoxication, and increased subjective intoxication, but it is unknown how cannabis concentrates may interact with alcohol to influence these outcomes. There is also a lack of research regarding whether timing or order of use matters, though recent survey data from our group and others suggests that using alcohol before cannabis may confer additional risk compared to using cannabis prior to alcohol. The present study leverages a federally-compliant mobile laboratory design to explore the acute effects of self-administered cannabis concentrates alongside a standardized dose of alcohol. The investigators will recruit a community sample of individuals who regularly use alcohol and cannabis to participate study sessions in our mobile laboratory. The sessions will involve individuals consuming cannabis concentrates of their choice (that they acquire themselves) along with a standardized dose of alcohol. Half of the participants will use the alcohol before cannabis, and the other half will use the cannabis before alcohol. The investigators will measure intoxication and biological outcomes every 30 minutes for 4 hours. The investigators will also measure differences between those who used alcohol before cannabis and those who used cannabis before alcohol.
- Conditions
- Alcohol Use Disorder, Cannabis Use
- Being tested
- commercially available cannabis administered prior to commercially available alcohol, commercially available alcohol administered prior to commercially available cannabis
- Keywords
- alcohol, cannabis, polysubstance use, psychomotor impairment, cannabis concentrates
- Medical subject headings
- Alcoholism, Marijuana Abuse, Psychomotor Disorders
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
commercially available cannabis administered prior to commercially available alcoholOther
Self administration of cannabis prior to researcher administered alcohol
commercially available alcohol administered prior to commercially available cannabisOther
Researcher administered alcohol prior to self-administration of cannabis
| Study group | Role | What they receive |
|---|---|---|
| Alcohol before Cannabis | Experimental | Participants are randomly assigned to receive the standardized alcohol dose during the experimental session prior to going inside their residence to self-administer their preferred cannabis concentrate product. Receives: Other: commercially available alcohol administered prior to commercially available cannabis |
| Cannabis before alcohol | Experimental | Participants are randomly assigned to go inside their residence to self-administer their preferred cannabis concentrate product and then receive the standardized alcohol dose. Receives: Other: commercially available cannabis administered prior to commercially available alcohol |
What is being measured
The primary outcome is the main question the study is designed to answer.
Breath Alcohol Level (BrAC)
Breath alcohol level will be measured using a breathalyzer repeatedly during the experimental session
Measured: Baseline (pre ingestion) and every 30 minutes (post ingestion) for a total of 270 minutes (9 measures)
Alcohol Urge Questionnaire (AUQ)
The AUQ is a self-report measure of urge for alcohol and has been validated for real-time assessment of alcohol craving in the laboratory. The total score on the measure ranges from 0-48 where higher is worse
Measured: Baseline (pre ingestion) and every 30 minutes (post ingestion) for a total of 270 minutes (9 measures)
Heart Rate (HR)
Heart rate (beats per minute) is measured using a finger pulse oximeter
Measured: Baseline (pre ingestion) and every 30 minutes (post ingestion) for a total of 270 minutes (9 measures)
ARCI Marijuana Scale
The ARCI scale measures subjective responses to cannabis. total score ranges from 0-12 where higher is worse
Measured: Baseline (pre ingestion) and every 30 minutes (post ingestion) for a total of 270 minutes (9 measures)
DRUID Psychomotor Battery
The DRUID is a mobile app that tests for cognitive and motor impairment, and has been shown to detect impairment related to alcohol and cannabis use. total score ranges from 0-100 where higher is worse.
Measured: Baseline (pre ingestion) and every 30 minutes (post ingestion) for a total of 270 minutes (9 measures)
Secondary outcomes (3)
Blood-THC
We will quantify levels of THC in the blood before and after the participant uses their cannabis product
Measured: Blood is drawn immediately prior to alcohol and cannabis consumption, again 60 minutes post alcohol administration start time, and again 240 minutes post alcohol start time
Biphasic Effects of Alcohol Scale (BAES)
The BAES measures the stimulating and sedating effects of alcohol and is validated for use in laboratory settings. This scale produces a stimulation subscale (total score ranges from 0-70 where higher is more stimulated) and a sedation subscale (total score ranging from 0-70 where higher is more sedated)
Measured: Baseline (pre ingestion) and every 30 minutes (post ingestion) for a total of 270 minutes (9 measures)
Profile of Mood States (POMS)
The POMS is a self-report rating scale that assesses state-level, distinct mood states. The POMS produces multiple subscales (Tension, depression, anger, fatigue, confusion, vigour, as well as a total mood disturbance scale)
Measured: Baseline (pre ingestion) and every 30 minutes (post ingestion) for a total of 270 minutes (9 measures)
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted21 Aug 2023
- Study start16 Dec 2021
- Primary completion1 Aug 2024
- Study completion1 Aug 2024
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Alcohol Use DisorderStudies of the same condition, open and under way.
- More trials run by University of Colorado, DenverThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Other
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- None (open label)
- Enrolment
- 146 participants (actual)
Sponsor and investigators
- Lead sponsor
- University of Colorado, Denver
- Sponsor type
- University, hospital or other
- Collaborators
- Institute of Cannabis Research, Colorado State University Pueblo, Colorado State University
- Responsible party
- Sponsor
- Investigators
- Hollis C Karoly, PhD, Principal investigator, University of Colorado, Denver
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT05999344
- Sponsor's protocol ID
- 2161
- Status last verified
- Nov 2025
- First submitted
- 11 Aug 2023
- Last updated
- 18 Nov 2025
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No
Study at a glance
From the registry record, last updated by the sponsor on 18 Nov 2025. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Exploring Intoxication During Acute Alcohol and Cannabis Concentrate Co-Administration: A Focus on Cannabinoid Content and Order Effects
- ClinicalTrials.gov ID
- NCT05999344
- Acronym / sponsor ID
- 2161
- Conditions
- Alcohol Use Disorder, Cannabis Use
- Keywords
- alcohol, cannabis, polysubstance use, psychomotor impairment, cannabis concentrates
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 146 participants (actual)
- Lead sponsor
- University of Colorado, DenverUniversity, hospital or other
- Collaborators
- Institute of Cannabis Research, Colorado State University Pueblo, Colorado State University
- Study start
- 16 Dec 2021 (actual)
- Primary completion
- 1 Aug 2024 (actual)
- Study completion
- 1 Aug 2024 (actual)
- First posted
- 21 Aug 2023 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
The goal of this study is to learn about the effects of combining alcohol with cannabis concentrate products which contain high levels of THC. The main question[s] it aims to answer are, 1) How does the order in which someone consumes THC and alcohol in a given co-use session impact outcomes such as blood alcohol level, heart rate or subjective drug effects, and 2) how does THC percentage in cannabis influence outcomes following alcohol and cannabis co-administration. Participants will be scheduled for our mobile lab to come to their residence. During the session, they will:
- consume a standardized dose of alcohol as well as use their own preferred cannabis concentrate product.
- they will then remain in our mobile lab for about 4 hours and complete some surveys as well as do some cognitive tasks on an iPad every 30 minutes.
- They will also have their blood drawn three times throughout the session, and will periodically be asked to blood into a breathalyzer to measure blood alcohol level.
Researchers will compare people who use alcohol prior to cannabis to those who use cannabis prior to alcohol to determine whether order of use impacts outcomes.
Detailed description
Individuals who drink alcohol commonly report co-using cannabis, and the increasing availability of new formulations of highly potent cannabis products on the legal market means that alcohol is likely being combined with cannabis products that contain high levels of delta-9-tetrahydrocannabinol (THC). There is limited existing research on the acute effects of cannabis products containing high amounts of THC, such as cannabis concentrates, which often contain up to 90% THC. Existing laboratory data suggests that consuming alcohol and cannabis together (compared to alcohol alone) is associated with reduced BAC, delayed time to peak blood alcohol concentration (BAC), longer duration of intoxication, and increased subjective intoxication, but it is unknown how cannabis concentrates may interact with alcohol to influence these outcomes. There is also a lack of research regarding whether timing or order of use matters, though recent survey data from our group and others suggests that using alcohol before cannabis may confer additional risk compared to using cannabis prior to alcohol. The present study leverages a federally-compliant mobile laboratory design to explore the acute effects of self-administered cannabis concentrates alongside a standardized dose of alcohol. The investigators will recruit a community sample of individuals who regularly use alcohol and cannabis to participate study sessions in our mobile laboratory. The sessions will involve individuals consuming cannabis concentrates of their choice (that they acquire themselves) along with a standardized dose of alcohol. Half of the participants will use the alcohol before cannabis, and the other half will use the cannabis before alcohol. The investigators will measure intoxication and biological outcomes every 30 minutes for 4 hours. The investigators will also measure differences between those who used alcohol before cannabis and those who used cannabis before alcohol.
Study design
- Primary purpose
- Other
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- None (open label)
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| Alcohol before Cannabis | Experimental | Other: commercially available alcohol administered prior to commercially available cannabisParticipants are randomly assigned to receive the standardized alcohol dose during the experimental session prior to going inside their residence to self-administer their preferred cannabis concentrate product. |
| Cannabis before alcohol | Experimental | Other: commercially available cannabis administered prior to commercially available alcoholParticipants are randomly assigned to go inside their residence to self-administer their preferred cannabis concentrate product and then receive the standardized alcohol dose. |
Who may qualify
- Ages
- 21 to 65 years
- Sex
- All
- Healthy volunteers
- Accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (5 listed)
- 21-65 years old,
- Heavy drinkers (for men, >4 drinks in one occasion, or >14 drinks per week; for women, >3 drinks in one occasion, or >7 drinks per week)
- Regular users of legal-market cannabis (at least 3x/week in past 3 months)
- Have experience using cannabis concentrates within the last year
- Willing to obtain a concentrate product of their choice for use in the study.
Key exclusion criteria (7 listed)
- Diagnosed with or seeking treatment for alcohol use disorder (AUD) or other substance use disorder (SUD)
- Pregnant, breastfeeding or trying to become pregnant
- Meet criteria for psychotic, bipolar or major depressive disorder with suicidal ideation, or history of these disorders
- Current use of psychotropic (except anti-depressants) or steroid medications
- Report illicit drug use in past 60-days or fail drug screen (drug screen tests for the presence of amphetamines, benzodiazepines, cocaine, THC, methamphetamine and opioids; only THC is allowed to be present in urine in order to be eligible to participate in the study
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| commercially available cannabis administered prior to commercially available alcoholSelf administration of cannabis prior to researcher administered alcohol | Other | Cannabis before alcohol |
| commercially available alcohol administered prior to commercially available cannabisResearcher administered alcohol prior to self-administration of cannabis | Other | Alcohol before Cannabis |
Primary outcome
Breath Alcohol Level (BrAC)
Time frame: Baseline (pre ingestion) and every 30 minutes (post ingestion) for a total of 270 minutes (9 measures)
Breath alcohol level will be measured using a breathalyzer repeatedly during the experimental session
Alcohol Urge Questionnaire (AUQ)
Time frame: Baseline (pre ingestion) and every 30 minutes (post ingestion) for a total of 270 minutes (9 measures)
The AUQ is a self-report measure of urge for alcohol and has been validated for real-time assessment of alcohol craving in the laboratory. The total score on the measure ranges from 0-48 where higher is worse
Heart Rate (HR)
Time frame: Baseline (pre ingestion) and every 30 minutes (post ingestion) for a total of 270 minutes (9 measures)
Heart rate (beats per minute) is measured using a finger pulse oximeter
ARCI Marijuana Scale
Time frame: Baseline (pre ingestion) and every 30 minutes (post ingestion) for a total of 270 minutes (9 measures)
The ARCI scale measures subjective responses to cannabis. total score ranges from 0-12 where higher is worse
DRUID Psychomotor Battery
Time frame: Baseline (pre ingestion) and every 30 minutes (post ingestion) for a total of 270 minutes (9 measures)
The DRUID is a mobile app that tests for cognitive and motor impairment, and has been shown to detect impairment related to alcohol and cannabis use. total score ranges from 0-100 where higher is worse.
3 secondary outcomes
Blood-THC
Time frame: Blood is drawn immediately prior to alcohol and cannabis consumption, again 60 minutes post alcohol administration start time, and again 240 minutes post alcohol start time
Biphasic Effects of Alcohol Scale (BAES)
Time frame: Baseline (pre ingestion) and every 30 minutes (post ingestion) for a total of 270 minutes (9 measures)
Profile of Mood States (POMS)
Time frame: Baseline (pre ingestion) and every 30 minutes (post ingestion) for a total of 270 minutes (9 measures)
Results and safety
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 18 Nov 2025.
- Individual participant dataSharing planned: No
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
Hollis C Karoly, PhD principal investigator
University of Colorado, Denver
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing commercially available cannabis administered prior to commercially available alcohol and commercially available alcohol administered prior to commercially available cannabis in people with Alcohol Use Disorder and Cannabis Use, run by University of Colorado, Denver at 1 site in United States.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 5 inclusion and 7 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: finished, as of the sponsor's last update on 18 Nov 2025. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in United States. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Breath Alcohol Level (BrAC) (time frame: Baseline (pre ingestion) and every 30 minutes (post ingestion) for a total of 270 minutes (9 measures)). The study lists 5 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 18 Nov 2025.