The smoking cessation drug varenicline (Chantix) can significantly reduce alcohol use in smokers who drink heavily, a new study suggests.

Researchers at the Ernest Gallo Clinic and Research Center at the University of California, San Francisco, studied 64 adults who were seeking treatment for smoking, but not drinking. They were randomly assigned to take either Chantix or a placebo. At the end of the 16-week study, those who took Chantix had reduced their average number of alcoholic drinks each week by 36 percent, compared with those who took a placebo, Newswise reports.

There was no correlation between the average number of drinks per week a person had, and the average number of cigarettes they smoked. This suggests that the drug’s effect on drinking was separate from its effect on smoking, the article notes.

Taking Chantix did not change the number of times per week study participants drank, but they drank less once they started, noted lead author Jennifer Mitchell, PhD. “If your usual pattern was to come home and have a few beers, you would still do that, but you might have one or two instead of four or five,” she said in a news release.

Research has previously shown that alcohol and nicotine act through a common pathway in areas of the brain that provide a sense of reward and pleasure, the researchers said. Chantix blocks the pleasant effects of nicotine in the brain.

The study appears in the journal Psychopharmacology.

Chantix has been controversial because of its potential side effects. In July 2009, the U.S. Food and Drug Administration (FDA) required that the drug carry a “black box” warning about the potential risks of depression and suicidal thoughts. In June 2011, the FDA said the drug may be associated with a small, increased risk of certain heart problems in patients with heart disease.