A new study casts sobering doubts on earlier claims that an alcoholism drug can truly treat the addiction.
The study, appearing in the Dec. 13 issue of
The New England Journal of Medicine, says naltrexone fails to prevent drinking relapses as well as previously believed, and, in fact, is no better than sugar pills at keeping hardened alcoholics on the wagon.
Dr. Robert Rosenheck, a Yale University psychiatrist and a study co-author, says he and his colleagues were "totally flabbergasted" by their findings. "Our study has to reduce the confidence that one can have in prescribing this medication," Rosenheck says. "But we don't have a definite answer yet."
The government is now sponsoring a large trial comparing naltrexone, which also is used to treat heroin addiction, with another alcoholism drug, acamprosate. Both medications act on the brain's opioid receptors to make drinking less pleasurable.
The Food and Drug Administration (FDA) approved naltrexone to treat alcoholism in 1994, marking the first new medication for problem drinking since 1948. At that time, the only other drug therapy available was disulfiram, or Antabuse, which provokes nausea in people who drink alcohol.
Alcoholism affects nearly one in 10 Americans, killing 100,000 people each year through illness, traffic accidents and other factors. The addiction leads to as much as $166 billion a year in direct and indirect health-care and social costs.
Earlier studies, including the work that led to its FDA approval, showed that, when combined with counseling, naltrexone could help suppress cravings and prevent relapses by reducing the number of days a person would drink and increasing the number of days between drinks.
In fact, the latest research was intended to learn not whether the drug was effective, which was assumed, but for how long. It also sought to determine if naltrexone paid for itself by reducing the need for other health services, Rosenheck says.
The new study involved 627 veterans, nearly all men who'd been drinking heavily since their 20s. The subjects, whose average age was about 49, said they'd typically been consuming about 13 drinks a day. Most had a family history of alcoholism.
The veterans were split into three groups: some took 50 milligrams a day of naltrexone for three months, some took the same dose for a year, and the rest were given sugar pills. All also were offered counseling, help taking their medication and referrals to Alcoholics Anonymous.
After 13 weeks, vets in the two naltrexone groups had an average time to relapse of 72 days, compared with 62 days for those who didn't take the drug -- an insignificant difference, the researchers say. And after a year, the drug was no better than the placebo at cutting the number of drinking days or total drinks taken, although all three groups had small declines in each measure.
While Rosenheck says the results are a "very loud 'no' in a chorus of fairly positive 'yeses,'" other researchers suggest the nature of the study population might have biased the findings against the drug. However, Rosenheck says every time his team goes back to the data to address these questions, it comes up with the same answer: "We can't make an evidence-based recommendation to use this medication."
But Raye Litten, chief of treatment research at the National Institute on Alcohol Abuse and Alcoholism, says the latest findings are merely "one more piece in a puzzle" whose broader outlines reveal an effective medication.
"We do know that naltrexone isn't a magic bullet, and we never said it was. It has small to medium effects and works in many but not all [alcoholics]. We're trying to figure out which ones it works best in," Litten says.
The fact that the study subjects were such hard-core drinkers might have warranted using more of the drug, perhaps double or triple the 50 milligram dose, Litten says.
What To Do
To learn more about alcoholism, visit the National Institute on Alcohol Abuse and
Alcoholism or the Screening for Mental Health, Inc..
If you think you've got a problem, perhaps you should consider Alcoholics Anonymous.