WASHINGTON — The antismoking drug varenicline also appears to curb alcohol cravings in smokers who are heavy drinkers, results of a small study show.
Nondependent heavy drinkers taking varenicline (Chantix) were nine times more likely to be abstinent during the 2-hour period of free access to alcoholic drinks than were those in the placebo group, based on logistic regression analysis, Sherry A. McKee, Ph.D., reported at a joint meeting sponsored by the Research Society on Alcoholism and the International Society for Biomedical Research on Alcoholism.
Participants were male and female non-treatment seeking, nondependent heavy drinkers who also were daily smokers, said Dr. McKee of Yale University, New Haven, Conn.
Subjects were titrated to steady-state levels of varenicline (2 mg/day) or placebo over the course of a week. On day 8, all participants were given free access to cigarettes and were administered a priming drink, which was designed to raise blood alcohol levels to 0.03 g/dL.
Subjective and psychological responses to alcohol were then assessed. A 2-hour period of self-administration followed, during which time participants could choose to consume up to eight additional drinks (designed to raise blood alcohol levels by 0.015 g/dL) or to receive monetary reinforcement for drinks not consumed.
Participants had to have smoked at least 10 cigarettes/day for the last year. Men had to consume more than 14 drinks/week or 5 or more drinks on one occasion; women had to consume more than 7 drinks/week or 4 or more drinks on one occasion. Urine testing was used to assess varenicline compliance on days 4–8.
A total of 20 participants were enrolled—10 in each arm. The groups were matched in terms of age, gender, number of cigarettes per day, weekly frequency of drinking, and number of drinks per episode.
During the period of unrestricted access to alcohol, varenicline “significantly reduced drinking by about two drinks,” Dr. McKee said. Two subjects in the varenicline group consumed drinks, compared with seven in the placebo group. After the priming drink, no difference was found in blood alcohol levels between the two groups. However, a significant difference was found in alcohol craving. Those on varenicline reported a sharp decrease in alcohol craving; those on placebo reported an increase.
The subjective effects of alcohol remained steady for those in the varenicline group but increased in the placebo group. The difference was statistically significant. There was no effect of varenicline on tobacco craving in this period.
Adverse events were few and included nausea, sleep disturbance, abnormal dreams, constipation, flatulence, and vomiting. Dr. McKee said that she had no conflicts of interest.