Varenicline works by latching onto the same receptors in the brain that nicotine binds to when cigarette smoke is inhaled. Pfizer developed the drug as a stop-smoking aid and has sold it in the US since August under the name Chantix.
A single pill appears to hold promise in curbing the urges to both smoke and drink, according to researchers trying to help people overcome addiction by targeting a pleasure center in the brain.
The drug is already sold to help smokers kick the habit. New but preliminary research suggests it could gain a second use in helping heavy drinkers quit, too.