Alcoholics who were given a medication approved for quelling nausea were able to cut back on their alcohol intake, researchers reported this week. The medication, ondansetron (Zofran), could become a readily available therapy for helping some alcoholics become abstinent.
The study, published Wednesday in the American Journal of Psychiatry, is based on research on a gene known as 5-HTT that is important to the serotonin system of the brain. Certain variants of this gene can increase the risk of psychiatric disorders, such as depression, anxiety, obsessive-compulsive disorder and addiction.
Ondansetron is used to prevent nausea and vomiting caused by cancer chemotherapy. But it's in a class of medications that work by blocking serotonin. The study tested the idea that a drug to block this neurotransmitter in genetically susceptible people might reduce the severity of their drinking.
Researchers analyzed the genotype of 283 alcoholics who were still drinking. They found that those with the 5-HTT LL genotype who received ondansetron took fewer drinks per day and had more days of abstinence over the 11-week study compared with people with the LL genotype who did not receive the drug. All the study participants received cognitive-behavioral therapy aimed at helping them become abstinent.
Among the patients who received ondansetron, those with the LL genotype or another variant called LL/TT cut back on their drinking enough to move out of the "high-risk" category of drinkers. But the drug did not seem to help patients who had other forms of the 5-HTT genotype.
The study was led by Bankole A. Johnson, chairman of the department of psychiatry and neurobehavioral sciences at the University of Virginia, and an expert in medications used to treat addiction. His paper on the use of topiramate - an anti-seizure medication - to treat alcoholism was published in the Journal of the American Medical Association in 2007.
In an e-mail, Johnson said that ondansetron had a stronger effect on promoting abstinence than topiramate in the LL genotype group. "Genotyping is becoming more common place and inexpensive," he said, opening the door to tailoring addiction treatment based on an individual's genes.