OBJECTIVE This longitudinal study examined the prevalence and correlates of energy drink use among college students, and investigated its possible prospective associations with subsequent drug use, including nonmedical prescription drug use. METHODS Participants were 1,060 undergraduates from a large, public university who completed three annual interviews, beginning in their first year of college. Use of energy drinks, other caffeinated products, tobacco, alcohol, and other illicit and prescription drugs were assessed, as well as demographic and personality characteristics. RESULTS Annual weighted prevalence of energy drink use was 22.6%(wt) and 36.5%(wt) in the second and third year of college, respectively. Compared to energy drink non-users, energy drink users had heavier alcohol consumption patterns, and were more likely to have used other drugs, both concurrently and in the preceding assessment. Regression analyses revealed that Year 2 energy drink use was significantly associated with Year 3 nonmedical use of prescription stimulants and prescription analgesics, but not with other Year 3 drug use, holding constant demographics, prior drug use, and other factors. CONCLUSIONS A substantial and rapidly-growing proportion of college students use energy drinks. Energy drink users tend to have greater involvement in alcohol and other drug use and higher levels of sensation-seeking, relative to non-users of energy drinks. Prospectively, energy drink use has a unique relationship with nonmedical use of prescription stimulants and analgesics. More research is needed regarding the health risks associated with energy drink use in young adults, including their possible role in the development of substance use problems.