Alcohol and Cannabis Concentrates Co-Administration

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.

Inclusion criteria

• 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.

Exclusion criteria

• 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.