THURSDAY, May 15, 2003 (HealthDayNews) -- In what's being called a potential breakthrough in alcoholism treatment, researchers say an anti-seizure drug dramatically reduced drinking among alcoholics who were drinking heavily when they started taking the drug.
Those who took topiramate, approved by the U.S. Food and Drug Administration to prevent epileptic and other seizures, were six times as likely as those who took placebo to abstain from drinking for at least four consecutive weeks during a 12-week study, say researchers at the University of Texas Health Science Center in San Antonio.
The study, reported in the May 17 issue of The Lancet, also found those who took the placebo were four times as likely as those who took topiramate to drink heavily for 28 consecutive days.
"The strength of the results is quite marked and dramatic, and they
would suggest to me that this drug may be more effective than anything we
currently have out for treating alcoholism," says lead researcher Dr. Bankole A. Johnson.
"We were surprised at the strength of the results because they are
very promising," says Johnson, a professor of psychiatry and
pharmacology and director of the Health Science Center's South Texas
Addiction Research and Technology Center.
"These are very heavily dependent patients, all alcoholics. The
critical factor here is not only were they all heavily dependent on alcohol,
but they were all still drinking heavily," Johnson adds.
Johnson says existing drugs for alcoholism -- antabuse, which makes
patients sick if they drink, and naltrexone, which blocks the pleasure
sensations from alcohol -- are designed mainly to prevent relapse among
alcoholics who stop drinking. Topiramate, by contrast, helps alcoholics quit
by blocking the "high" from alcohol while reducing withdrawal symptoms and cravings, Johnson says.
Topiramate is made by Ortho-McNeil and is sold under the brand name Topamax.
Researchers defined drinking heavily as more than five drinks a day
for men and more than four for women.
The clinical trial began with 150 alcoholic patients -- 75
received topiramate while the rest got a placebo. In addition to medication or placebo, patients also had weekly counseling sessions, typically about 20 minutes, emphasizing that taking medication as directed is critical to changing drinking behavior.
Of the 55 patients who completed the trial in the topiramate group,
13, or nearly 24 percent, remained abstinent for 28 consecutive days,
compared with just two, or about 4 percent, in the placebo group.
And those taking topiramate abstained from drinking an average of
eight weeks, twice as long as those taking the placebo.
The study found topiramate appears to markedly reduce the effects of dopamine, believed to create the pleasurable sensations from alcohol, by acting on two key brain chemicals. The drug simultaneously increases the amount of the brain chemical gamma-amino butyric acid and blocks the activity of another brain chemical, glutamate, researchers say. Both effects diminish the release of dopamine in the brain.
Excessive glutamate in the brain is believed to contribute to
alcohol withdrawal symptoms such as shakiness, so topiramate also significantly eases withdrawal from alcohol and reduces cravings, the study says.
Patients ranged from 21 to 65 years of age; men reported
drinking an average of 35 drinks a week, while women averaged 21 drinks a week during the 90 days preceding enrollment in the study. How long a patient had been an alcoholic had no effect on topiramate's effectiveness, the researchers found.
The study notes alcohol consumption figures are based not only
on self-reporting by patients but also on lab tests measuring recent alcohol
use.
The Texas researchers' findings generated considerable excitement among alcoholism experts, who say topiramate could represent a major advance in treatment.
Dr. Robert Malcolm, associate dean and a professor of psychiatry and
family medicine at the Center for Drug and Alcohol Programs at the Medical
University of South Carolina, says topiramate could change the
direction of alcohol treatment.
Unlike previous research that studied patients who took drugs after
they stopped drinking, the topiramate study started with alcoholics who were
still drinking, Malcolm notes.
"In a sense, the [topiramate] researchers are taking a more unstable group of patients and getting a reduction in drinking behavior and abstinence among these patients who are coming in drinking," he says. "So it's a very real-world type of model."
If further research with more subjects bears out the study's findings, Malcolm predicts topiramate will become an effective alcoholism drug that could be prescribed by primary-care doctors, without the need for extensive counseling.
"What this means is that if these findings hold up that very
shortly, physicians. . . using this or a similar drug are going to have a
major impact on treating alcohol-abuse problems in their office, without
sending people away to treatment centers," Malcolm says.
Nearly 14 million Americans abuse alcohol or are alcoholic, says the
National Institute on Alcohol Abuse and Alcoholism. Several million more
adults engage in risky drinking such as binge drinking and heavy drinking
regularly, the institute says.
More information
For more on alcohol abuse, alcoholism and treatment, visit the National Institute on Alcohol Abuse and Alcoholism or the American Academy of Family Physicians.
