Treating alcohol abuse
By the faculty of Harvard Medical School for The Harvard Medical School Adviser

Q: What medications can help alcoholics stay sober, and how do they work?

A: Staying sober can be very challenging for people with alcoholism (see illustration). In 2005, the National Institute on Alcohol Abuse and Alcoholism updated its guidelines for doctors. The guidelines encourage doctors to consider medication in addition to behavioral therapy for people who are dependent on alcohol or who have recently stopped drinking but are experiencing cravings or "slips."

More than 50 clinical studies of drugs and plant extracts to treat alcohol dependence are now under way. But as of 2007, the Food and Drug Administration has approved only three drugs for this purpose. They are disulfiram (Antabuse), naltrexone (ReVia, and an injectable form of the drug, Vivitrol) and acamprosate (Campral).

Whether someone should take medication, which one to take and what dose to use depend on a number of factors. The drugs work in different ways, and alcohol affects each person differently. As such, a person may respond better to one medication than another. Here is a brief rundown on each:

Disulfiram (Antabuse): Disulfiram blocks an enzyme that helps break acetaldehyde, a chemical made by the body when you drink alcohol. If you drink while taking disulfiram, acetaldehyde builds up in your bloodstream, causing flushing, headache, nausea and vomiting. The drug discourages alcohol use by making you ill if you drink. But it doesn't eliminate your desire for alcohol. The drug can sometimes cause chest pain, increased blood pressure and, in rare instances, cardiac arrest and death. People with serious health problems such as heart disease, diabetes or liver disease shouldn't take it. People who take disulfiram need regular blood tests to check their liver health. The drug has few side effects in people who are not drinking, however. Disulfiram seems to be effective for older, severely alcoholic men who are monitored carefully by family members and professionals.

Naltrexone (ReVia, Vivitrol): Naltrexone reduces your craving for a drink. And, if you do drink, the drug blunts the pleasurable effects of alcohol. Doctors generally recommended naltrexone for people who have stopped drinking and are trying to avoid a relapse. But some people who have not been able to abstain completely may use it to control their drinking. In many, but not all, studies of this drug, people taking naltrexone abstained from alcohol longer and had fewer relapses than those taking a placebo (dummy pill). An analysis of 29 studies found that naltrexone reduced the risk of relapse or a return to heavy drinking by more than one-third during the first three months after withdrawal. But the effect only lasts while the person is taking the drug. Like disulfuram, people taking naltrexone need blood tests to check their liver health.

Naltrexone used to be available only in pill form. But some people who are alcohol-dependent have difficulty sticking to a daily medication schedule. In mid- 2006, the FDA approved an extended-release formulation of naltrexone called Vivitrol, which is given by injection once a month in a doctor's office. In one six-month study, researchers at Harvard Medical School compared this treatment to a placebo. Both groups of patients also underwent psychotherapy. Injected naltrexone reduced heavy drinking by about 25 percent and also boosted the rate of abstinence.

Acamprosate (Campral): Scientists are not sure how acamprosate works. But they believe it affects two brain chemicals (neurotransmitters) in a way that diminishes the unpleasant symptoms of long-term abstinence, such as restlessness, anxiety and insomnia. In so doing, the drug may reduce cravings. To take this drug, you need to have normal kidney function, which can be checked with a simple blood test.

Acamprosate is approved for people who have quit drinking and are also receiving some form of psychotherapy. It may not be effective in people who are actively drinking or are abusing other substances. Many studies show the drug boosts abstinence rates among those who are alcohol dependent and have recently undergone detoxification.

Drug therapy for alcoholism is a very active area of research, so there's good reason to hope that additional -- and perhaps more effective -- medications or combinations of medications will become available in the future. Everyone who has watched a friend or relative struggle against alcohol abuse will raise a toast to that -- nonalcoholic, of course.

Copyright 2007 the President and Fellows of Harvard College. Developed by Harvard Health Publications (www.health.harvard.edu). Distributed by UFS. Submit q u e s t i o n s t o harvard_adviser@hms.harv ard.edu.