E-cigarette use of young adults motivations and associations with combustible cigarette alcohol, marijuana, and other illicit drugs.

Although the potential harm associated with e-cigarettes remains largely unknown, e-cigarettes appear to be a risk marker for the use of substances that are known to pose substantial health problems. Health care providers should screen for e-cigarette use, and youth substance use prevention programs should target the reduction of e-cigarette use with particular attention to addressing their taste appeal. (Am J Addict 2017;26:343-348).