Simultaneous Use of Alcohol and Marijuana: Patterns and Individual Differences

Abstract

Background: Simultaneous alcohol and marijuana (SAM) use, or using alcohol and marijuana in such a way that their effects overlap, is associated with negative health and behavioral outcomes. Objectives: Our study sought to fill gaps in our knowledge on this emerging public health concern by comparing SAM users and alcohol-only users on individual-level factors and substance use outcomes as well as examining associations of SAM use frequency, within users. Methods: Participants were recruited through online postings. Our analytic sample consisted of 1,017 young adults (18-25 years) who reported past-month alcohol use. Most were male (67.8%), Caucasian (71.5%), and had attended at least some college (74.8%). Results: Past-year SAM users reported higher levels of sensation seeking and greater perceptions of their close friends' drinking behavior in comparison to alcohol-only users. SAM users reported heavier and more frequent alcohol use than alcohol-only users. Within past-year SAM users, 70% reported SAM use at least weekly. More frequent SAM use was associated with all alcohol use outcomes (e.g., weekly quantity, frequency, alcohol-related problems) and marijuana use outcomes (e.g., quantity, frequency, peak use) and higher drinking norms. Conclusions/Importance: It is clear that SAM users are a vulnerable sub-population of young adult drinkers. SAM users are differentiated from alcohol-only users in terms of their personality characteristics and perceptions of peer groups' drinking. SAM users and more frequent users are also at heightened risk for substance use outcomes. Prevention and intervention efforts targeting high-risk drinking may benefit from also assessing whether they simultaneously use alcohol and marijuana.

Motives for Alcohol and Marijuana Use as Predictors of Use and Problem Use Among Young Adult College Students

“…On the contrary, alcohol use levels did not correlate with marijuana use levels or subsequent problem use of marijuana. Collectively, only to a limited extent do these findings coincide with the literature that suggests that alcohol and marijuana co-use may serve as a catalyst for increased use of both substances (Gunn et al, 2018;Linden-Carmichael et al, 2019;Metrik et al, 2018;Patrick et al, 2017, Patrick, Kloska et al, 2018. Nevertheless, these findings underscore the critical need to address college student co-users.…”

A Daily Study Comparing Alcohol‐Related Positive and Negative Consequences for Days With Only Alcohol Use Versus Days With Simultaneous Alcohol and Marijuana Use in a Community Sample of Young Adults

“…Most young adults who use marijuana also use alcohol (Patrick et al, ), and recent research indicates simultaneous use of alcohol and marijuana is associated with greater alcohol use compared to drinking occasions without using marijuana among veterans (Metrik et al, ). SAM users have been found to be higher on risk factors such as perceived norms of peer SAM use and sensation seeking (e.g., Linden‐Carmichael et al, ; White et al, ).…”

Does the Combination Matter? Examining the Influence of Alcohol and Cannabis Product Combinations on Simultaneous Use and Consequences in Daily Life

“…Compared to co‐users who do not use both substances together or mono‐substance users, SAM users have reported higher levels of consumption (Brière et al, 2011; Gunn et al, 2018; Linden‐Carmichael et al, 2019; Metrik et al, 2018; Subbaraman and Kerr, 2015) and more negative consequences (Brière et al, 2011; Jackson et al, 2020; Midanik et al, 2007; Subbaraman and Kerr, 2015; Yurasek et al, 2017). In particular, SAM users were shown to be more likely to endorse 9 types of consequences, relative to alcohol‐only users, with the strongest effects observed for more acute consequences (e.g., blackouts; Jackson et al, 2020).…”