The Role of Nicotine and Non-Nicotine Alkaloids in E-Cigarette Use and Dependence

The advent of electronic cigarette (e-cigarette) technologies represents one of the most significant developments in the last several decades, and provides a novel and promising strategy for substantially reducing the morbidity and mortality associated with smoking. However, serious concerns have been raised regarding the possibility that e-cigarettes will sustain a dependency on nicotine and that they may lead to continued use of conventional cigarettes known to be extremely harmful to health. Cigarette addiction critically involves a dependence on nicotine, but it is likely that other tobacco constituents contribute to dependence as well. Recent evidence suggests that non-nicotine tobacco alkaloids, or NNTAs (including anabasine, anatabine, nornicotine, and myosmine) may play a role in tobacco dependence. These alkaloids have been shown to augment the reinforcing effects of nicotine in animal models and to affect cravings in human smokers. E-cigarettes contain variable quantities of nicotine and NNTAs, but there is virtually no information available concerning the role of e-cigarette nicotine or NNTA content in influencing the concurrent use of cigarettes and e-cigarettes, when smokers attempt to switch from conventional combustible cigarettes to e-cigarettes. Additionally, it is not known whether the presence of nicotine and NNTAs in e- cigarettes may sustain dependence, making it difficult to relinquish these products. The proposed project will assess the acceptability, extent of switching behavior, and degree of dependence maintained when smokers are provided with e-cigarettes containing nicotine and NNTAs.