A Critical Review of Repurposing Apomorphine for Smoking Cessation

Tobacco use disorder is the leading cause of preventable death and disability in the United States, with one in five Americans currently smoking cigarettes. Only two non-nicotine medications are FDA approved for treating tobacco use disorder, and advances in drug discovery are profoundly outpaced by the morbidity and mortality caused by tobacco dependence. Drug repurposing may provide an approach for addressing this health hazard, offering hope to tobacco users attempting to quit who have failed existing therapies. The focus of this review is to evaluate the potential role of apomorphine (APO) in treating tobacco dependence. Previously described in the literature as a non-specific dopamine agonist effective in treating Parkinson's disease and erectile dysfunction, APO's dopaminergic targeting activity may be effective in counteracting the modified response arising from tobacco use. Here, the literature describing APO's activity is reviewed and presented in the context of known nicotine-induced response in neurotransmitter systems. Based on these data, whether APO may be an effective smoking cessation agent by ameliorating a tobacco user's anhedonic state is critically appraised, along with withdrawal symptoms and the chemical reinforcement associated with drug-seeking behaviors.