Motivations for Tobacco, Cannabis, and Their Co-Use Among US Young Adults Who Engage in Same-Day Co-Use

Objectives: The purpose of this study was to identify more detailed use behaviors and motivations for same-day co-use of tobacco and cannabis among U.S. young adults, compared to previous literature on co-use. Methods: We conducted an online cross-sectional survey among N = 303 U.S. young adults (ages 18-30, mean 25.9) during February 2024 through Prolific. The questions included co-use behaviors of tobacco and cannabis within the same day, and motivations for tobacco, cannabis, and their co-use. Using R, paired two-sample t-tests were used to compare mean differences of separate motivations to use measures for cannabis and tobacco among participants with same day co-use. Results: Among participants who reported past-30-day co-use of tobacco and cannabis (n = 176), a majority (94%; n = 160) reported same-day co-use. Participants who engaged in same-day co-use (n = 160) reported craving nicotine (60%), craving cannabis (54%), and feeling stressed (49%) as reasons for co-use. Among participants who engaged in same-day co-use, motivations for using cannabis (vs. tobacco) were higher for the level of effect, satisfying feeling, control over how much used, time to feel the effect, liking, purity, price, variety of product, amount to feel the effect, feeling less judged (p's < 0.024), and motivations for using tobacco (vs. cannabis) were higher for convenience, when feeling angry, and when feeling uncomfortable or upset (p's < 0.044). Conclusions: Findings show that young adults may be co-using tobacco and cannabis on the same day due to cravings for both substances and stress and yet have different motivations for using cannabis and tobacco.