With the legalization of recreational marijuana in some areas, it is anticipated that more college students will combine marijuana use with alcohol consumption. The current study investigated whether students who combine marijuana and alcohol use differ in their motives and impairment compared to their peers who only use alcohol. All study participants were recruited from a private university in Washington, a state where recreational marijuana use is legal.
The authors surveyed 430 undergraduates about their alcohol and marijuana use, impairment, and motives for use. The sample was primarily female (81.2%) with a mean age of 20.6 (SD = 2.39). Measures included the Customary Drinking and Drug Use Record, the Drinking Motives Measure, the 18-item Rutgers Alcohol Problem Index, The Marijuana Smoking History Questionnaire, the 25-item Marijuana Motives Measure, and the 18-item Rutgers Marijuana Problem Index. The respondents were grouped into alcohol-only users (n = 279) or dual users (n = 151).
Results showed that among students who used alcohol by itself, social motives predicted use. Whereas, enhancement motives predicted alcohol and marijuana use among dual users. They also predicted impairment among these users. Among all types of users, frequency of use predicted more impairment. Finally, coping motives predicted more marijuana use, but not more alcohol use among dual users.
A limitation of the study is its homogenous sample that included mostly white women at a Christian university. As well, without longitudinal data about use and motives, it is not possible to uncover how motives may change over time. Finally, future studies could recruit marijuana-only users to discover how their motives may differ.
Take Away: Combination marijuana-alcohol users report enhancement motives as their reason for use. Alcohol-only users report social motives as more predominant.