Two medications could help tens of thousands of alcoholics quit drinking – yet the drugs are rarely prescribed to patients, researchers reported last week.

The medications, naltrexone and acamprosate, reduce cravings for alcohol by fine-tuning the brain’s chemical reward system. They have been approved for treating alcoholism for more than a decade. But questions about their efficacy and a lack of awareness among doctors have resulted in the drugs being underused, the researchers said.

Fewer than a third of all people with alcohol problems receive treatment of any kind, and fewer than 10 percent are prescribed medications. The Affordable Care Act requires insurers to provide coverage for substance-abuse treatments and services

George Koob, director of the National Institute on Alcohol Abuse and Alcoholism, said the new study should reassure doctors that naltrexone and acamprosate, while not a silver bullet, can help many patients.

In the new study, which was published in JAMA, a team of researchers based mostly at the University of North Carolina at Chapel Hill compiled findings from the most rigorous trials of medications for alcoholism in the past few decades.

The new research looked only at the effectiveness of the medications in combination with behavioral interventions such as counseling and therapy, which is how they are normally used. It was unknown whether the drugs would be as effective on their own.