The anti-smoking drug varenicline (Chantix) was found to significantly reduce alcohol use in a group of heavy-drinking smokers in a study at the Ernest Gallo Clinic and Research Center at the University of California, San Francisco.
“Alcohol abuse is a huge problem, and this is a big step forward in identifying a potential new treatment,” said senior author Howard L. Fields, M.D., Ph.D., professor of neurology and director of the Wheeler Center for the Neurobiology of Addiction at UCSF.
Study participants were seeking treatment for smoking, not drinking, and were randomly given either varenicline or a placebo. By the end of the study, volunteers taking varenicline had reduced their average number of drinks per week by 36 percent compared to those taking placebo.
Researchers found no link between the average number of drinks each participant consumed per week with the average number of cigarettes smoked, suggesting that the drug’s effects on drinking behavior were separate from its effects on smoking.
Although researchers noted that more studies are needed to further examine potential side effects, they are hopeful that varenicline will be used as a treatment for heavy drinking.
“The drug is already widely used by smokers to help them quit,” said Fields. “Many heavy drinkers also smoke, and this study indicated that, in this group, varenicline was effective in reducing both the number of cigarettes smoked and the number of drinks consumed.”
Interestingly, during the study, participants drank the same number of times per week as they did before, said lead author Jennifer Mitchell, Ph.D., clinical project director at the Gallo Center and an adjunct assistant professor of neurology at UCSF.
“People initiated drinking at the same rate, but they drank less once they started,” she said. “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.”
A drug that could reliably decrease alcohol consumption would be of great value in reducing the harm caused by alcohol abuse, said Mitchell.
“If you currently drink seven drinks a night, and we can turn that into two or three, then you’re not only drinking at a level that’s going to harm you less, you’re less likely to harm others, as well.
“If we could lower the rates of drunk driving, spousal and child abuse and other secondary effects of alcoholism, that would be tremendous.”
Researchers noted that the study confirms earlier research by the Gallo Center by showing that alcohol and nicotine work through a common pathway in areas of the brain that offer a feeling of pleasure and reward. Varenicline works by blocking the pleasurable effects of nicotine in the brain.
Few negative side effects were reported, suggesting that the drug can be well-tolerated, said Fields. However, researchers warned that the absence of significant side effects could be because study participants were thoroughly screened for mental disorders such as depression, anxiety and suicidal ideation, as well as alcoholism, before the study began.
They suggest that the drug be tested in populations with co-existing psychiatric conditions, as well as with nonsmoking alcohol abusers.
The study was published in the journal Psychopharmacology.