A new study shows that varenicline, already approved to help patients quit smoking, has the potential to turn users off alcohol as well.
The nicotine receptor partial agonist varenicline (Chantix) has been approved as a smoking cessation medication since 2006. By partially blocking nicotine’s ability to activate its receptors, the drug interferes with the pleasurable stimulation of the dopamine system enjoyed by smokers. A new study carried out by researchers at the University of Chicago suggests that varenicline may also have an impact on the effects of alcohol consumption.
Anecdotal reports from those taking varenicline and results from previous studies have indicated that the drug tends to reduce alcohol consumption, although the underlying mechanism by which it does so has been unclear. The current study was designed to determine whether the drug reduces the pleasurable aspects or increases the unpleasant aspects of drinking alcohol. (In addition to its merits as a smoking cessation medication, varenicline has also been implicated
in increasing the risk of adverse cardiovascular events in those with cardiovascular disease.)
The study, led by Emma Childs, PhD, a research associate at the University of Chicago Medical Center, included 8 men and 7 women between the ages of 21 and 45 years, with the majority in their mid-20s, all moderate to heavy social drinkers but not dependent on alcohol or nicotine. In order to participate, subjects had to consume at least 10 drinks per week and engage in at least 1 binge-drinking episode per week. On average, participants reported 7.8 binge-drinking episodes per month.
The participants took part in 6 sessions during each of which they consumed either 2 mg of varenicline or placebo followed 3 hours later by a drink containing placebo, a low dose of alcohol (0.4 g alcohol/kg of body mass), or a high dose of alcohol (0.8 g/kg). Tests were administered periodically, both before and after drink consumption, to measure subjective mood and perception of drug effects, heart rate and blood pressure, and eye-tracking ability.
Varenicline by itself increased blood pressure, heart rate, sense of dysphoria and nausea, and eye-tracking ability. For those who drank alcohol, varenicline increased dysphoria, reduced enjoyment of alcohol, and reduced eye-tracking impairment. In fact, varenicline increased the unpleasant effects of alcohol even after controlling for varenicline-induced nausea.
The results suggest that varenicline has the potential to reduce alcohol consumption by increasing the unpleasant effects of drinking it. The reduced impairment of eye tracking among those who drank alcohol after taking varenicline also suggests that the drug reduces the rewarding experience of drinking alcohol.
"The pleasurable effects of alcohol, for example feeling 'buzzed' and talkative, are associated with greater consumption and binge drinking,” said Dr. Childs in a press release. “Some people lose control of their alcohol consumption during a drinking episode, for example they may aim to only have one or two drinks but end up drinking say four or five. If varenicline counteracts these positive effects by producing unpleasant effects, then as a result people may consume less alcohol during a drinking episode."
was published online February 16, 2012, in Alcoholism: Clinical & Experimental Research
. (Registration is required for full-text access.)
Other resources to help patients quit:
Breaking the Cycle: How Smokers Can Improve Their Chances of Quitting
Text4health Takes AIM at Tobacco Use