Cannabinoid-nicotine interactions

Abstract

Although nicotine and delta-9-tetrahydrocannabinol (THC), the main psychoactive ingredients in tobacco and cannabis, bind to different receptors in the brain, they have several features in common. Each of these drugs is typically self-administered by smoking, and this behavior is maintained by rewarding effects that are mediated by brain circuitry that at least partially overlaps between the drugs. Each tends to be used chronically, leading to dependence and addiction in many users. Perhaps most importantly, the nicotinic and cannabinergic systems appear to interact in such a way that modulating one system can enhance or counteract effects of the other system. Therefore, studying cannabinoid-nicotine interactions could potentially lead to new treatments for addiction. This chapter considers such interactions, focusing on recent preclinical work that suggests manipulating the cannabinoid system can counteract the addictive effects of nicotine that manipulating the nicotinic system can counteract the addictive effects of cannabis, and that prior or concurrent use of cannabis has the detrimental effect of increasing the addictive effects of nicotine. Interactive effects of these systems on anxiety and memory are also considered, although these have been studied less than addiction-related effects.