THC Crossover Study

Experienced dual cannabis-tobacco smokers will participate in a within-subject crossover study with three blocks: smoked cannabis (purchased by participants from a local dispensary), dry herb cannabis vaporizer, and usual brand tobacco cigarette. Each block will consist of 2 consecutive days on an inpatient research ward. The first inpatient day of each block will comprise of two sessions: (1) The first session will be a standardized bout to compare pharmacokinetic, physiologic, and subjective effects of cannabis and tobacco use; (2) after 6 hours of abstinence, the second session will be ad libitum access to the assigned product for 2 hours to compare subjective effects (reward, satisfaction, craving reduction) and use patterns. The second inpatient day will consist of ad libitum use of the assigned product from 8:00 in the morning to midnight. An abstinence day will be added after the second day of the last block to assess exposure and effects biomarkers during a period of abstinence from cannabis (smoked/vaped) or tobacco.