Cannabis' Impact on Alcohol Consumption

Study Overview
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Brief Summary
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This study employs a repeated measures experimental design to examine the effect of THC-dominant dose of cannabis and CBD-dominant dose of cannabis, relative to placebo, on subsequent drinking in an alcohol choice task in which participants choose either to drink or receive monetary reinforcement for drinks not consumed. Cannabis will be administered simultaneously with an alcohol-priming dose or alcohol placebo. The study will enroll up to 350 nontreatment-seeking heavy episodic alcohol drinkers who use cannabis weekly.

Detailed Description
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This study employs a repeated measures experimental design to examine the effect of THC-dominant (9.53% THC and 0.09% CBD) dose of cannabis and CBD-dominant (0.35% THC and 11.27% CBD) dose of cannabis, relative to placebo, on subsequent drinking in an alcohol choice task in which participants choose either to drink or receive monetary reinforcement for drinks not consumed. Cannabis will be administered simultaneously with an alcohol-priming dose or alcohol placebo. The study will enroll up to 350 nontreatment-seeking heavy episodic alcohol drinkers who use cannabis weekly to obtain the final sample of 200 with complete data. Participants will be tested at a baseline session, during three experimental sessions, and then during a subsequent 4-week period in the natural environment using a smart-phone application. Findings have important implications for cannabis regulatory science and alcohol use disorder treatment by addressing the relative impact of specific cannabinoids as well as contextual risk in cannabis-alcohol co-use.

Official Title
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Cannabis' Impact on Alcohol Consumption: Integrating Laboratory and Ecological Momentary Assessment Methods

Conditions
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Alcohol Drinking, Cannabis Use, Cannabis, Alcohol Use Disorder

Intervention / Treatment
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* Drug: THC-dominant cannabis
* Drug: CBD-dominant cannabis
* Drug: Cannabis placebo
* Drug: Alcohol
* Drug: Alcohol placebo


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age 21 to 50 English-speaking cannabis smoking in past two months heavy drinking in past two months in good physical health and weighing < 250 lbs zero breath alcohol at each visit Exclusion Criteria: positive pregnancy test nursing positive urine toxicology screen for drugs other than cannabis interest to quit or receive treatment for cannabis or alcohol use

Ages Eligible for Study
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Minimum Age: 21 Years
Maximum Age: 50 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Basic Science
Allocation: Randomized
Intervention Model: Factorial Assignment
Interventional Model Description: Mixed factorial design will use a 3 (within-subjects; cannabinoid dose: 9.53% THC/0.06% CBD, 11.27% CBD/0.35% THC, placebo) X 2 (between-subjects; cannabis + an alcohol-priming dose (0.3 g/kg) versus cannabis + alcohol placebo)
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: THC-dominant cannabis dose<br>367 mg of cannabis plant material with 9.53% THC and 0.09% CBD and 217 mg of placebo cannabis plant material will be mixed and smoked in a handheld pipe | Drug: Alcohol<br>* Drink containing 0.3 g/kg of alcohol<br>Drug: Alcohol placebo<br>* Placebo beverage contains only juice and a negligible trace of alcohol for masking<br>|
| Experimental: CBD-dominant cannabis dose<br>367 mg of cannabis plant material with 11.27% CBD and 0.35% THC and 217 mg of placebo cannabis plant material will be mixed and smoked in a handheld pipe | Drug: Alcohol<br>* Drink containing 0.3 g/kg of alcohol<br>Drug: Alcohol placebo<br>* Placebo beverage contains only juice and a negligible trace of alcohol for masking<br>|
| Placebo Comparator: Placebo<br>584 mg of cannabis plant material will be smoked in a handheld pipe | Drug: Alcohol<br>* Drink containing 0.3 g/kg of alcohol<br>Drug: Alcohol placebo<br>* Placebo beverage contains only juice and a negligible trace of alcohol for masking<br>|
| Experimental: Alcohol priming dose<br>Alcohol: 0.3 g/kg. Alcohol priming drink is designed to raise blood alcohol levels to 0.03 g/dl and be consumed in 5 minutes. The drink is mixed using 80-proof liquor and juice. Participants are randomized to receive either the experimental alcohol priming dose or alcohol placebo. | Drug: THC-dominant cannabis<br>* Smoked cannabis with 9.53% THC and 0.09% CBD<br>Drug: CBD-dominant cannabis<br>* Smoked cannabis with 0.35% THC and 11.27% CBD<br>Drug: Cannabis placebo<br>* Smoked placebo cannabis plant material<br>|
| Placebo Comparator: Alcohol placebo dose<br>Placebo beverage contains only juice and a negligible trace of alcohol for masking. The weight and sex-adjusted volume of alcohol and non-alcohol containing beverages will be equal. Participants are randomized to receive either the experimental alcohol priming dose or alcohol placebo. | Drug: THC-dominant cannabis<br>* Smoked cannabis with 9.53% THC and 0.09% CBD<br>Drug: CBD-dominant cannabis<br>* Smoked cannabis with 0.35% THC and 11.27% CBD<br>Drug: Cannabis placebo<br>* Smoked placebo cannabis plant material<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| ml of alcohol consumed | ml of alcohol consumed during the alcohol choice task | post-smoking during two-hours of the alcohol choice task | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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alcohol, cannabis, marijuana, addiction, cannabinoid, tetrahydrocannabinol, cannabidiol