As indicated by Figure 2 and the literature (13), most cannabis users report a lifetime history of cigarette smoking. Cigarette smoking, however, is commonly reported in users of a variety of illicit psychoactive drugs (e.g. in NSDUH, over 90% of cocaine and methamphetamine users report cigarette smoking). Nonetheless, the co-occurring use of cannabis and tobacco may extend beyond the mechanisms underlying general co-use of substances. In the following sections, we describe evidence accumulating from the literature on the putative mechanisms connecting cannabis and tobacco use – an overview may be found in Figure 1.
