Pharmacological effects of naltrexone and intravenous alcohol on craving for cigarettes among light smokers: a pilot study

Rationale Although naltrexone has been widely researched in the context of drinking and smoking behaviors, with each substance studied separately, little is known about the effects of naltrexone on craving for cigarettes during alcohol intoxication. Objectives The present study used a within-subjects double-blind placebo-controlled design to (1) examine the effects of alcohol, administered intravenously, on craving for cigarettes; (2) test the effects of naltrexone on cigarette craving during alcohol intoxication; and (3) examine the relationship between craving for alcohol and cigarettes across rising breath alcohol concentrations (BrACs). Materials and methods Heavy drinking light smokers completed two counterbalanced intravenous alcohol challenge sessions, one after taking naltrexone (50 mg) for 3 days and one after taking a placebo for 3 days. During each session, participants reported on their craving for alcohol and cigarettes. Results Analyses revealed a significant positive effect of BrAC on urge to smoke as well as a BrACxMedication interaction. Specifically, the linear relationship between BrAC and urge to smoke was significantly weaker in the naltrexone condition, as compared to placebo. There was also a positive association between urge to drink and urge to smoke, and this relationship was moderated by BrAC. Conclusions These findings demonstrate that the pharmacological effects of alcohol alone induce craving for cigarettes and that naltrexone blunts the progression of craving for cigarettes during alcohol intoxication. These results highlight the potential clinical utility of naltrexone for heavy drinkers trying to quit smoking.