A drug that lowers the activity of serotonin and other chemical messengers in the brain may boost the effectiveness of psychological treatments for a severe form of alcoholism, at least over a short time period, a new study finds.
Ondansetron, a medication currently prescribed to quell nausea and vomiting in chemotherapy patients, helps to reduce drinking and foster abstinence among adults who developed alcoholism before age 25, report psychiatrist Bankole A. Johnson of the University of Texas Health Science Center in San Antonio and his colleagues.
“We think we’re dealing with a biological trait that creates a predisposition to early-onset alcoholism and perhaps other addictions,” Johnson says.
The researchers recruited volunteers seeking alcoholism treatment at either of two substance-abuse centers in Texas between 1995 and 1999. A total of 271 participants—many of them middle-age, white men—were assigned at random to receive one of three daily dosages of ondansetron or a placebo pill for 11 weeks. All volunteers also attended weekly group-psychotherapy sessions aimed at teaching them strategies to avoid alcohol use.
About 60 percent of people in each treatment group completed the trial. During the study, alcohol consumption was established through self-reports and chemical analyses of blood and urine. All groups exhibited noticeable drops in alcohol intake by the end of treatment and a greater tendancy to abstain from drinking.
Among the 161 patients with early-onset alcoholism, those who received ondansetron consumed less alcohol and spent more time abstinent than did those who got the placebo, Johnson’s team reports in the Aug. 23/30 Journal of the American Medical Association.
For example, volunteers taking the middle dose of ondansetron spent 70 percent of study days abstinent and imbibed an average of 1 1/2 drinks daily; those in the placebo group were abstinent 50 percent of the days and averaged nearly 3 1/2 drinks daily.
Participants with alcoholism that began later in life exhibited no greater improvement on ondansetron than on the placebo.
Ondansetron blocks the activity of serotonin directly, which leads to reductions in other neurotransmitters, including dopamine. However, the physiological mechanism that creates a disposition to early-onset alcoholism remains unknown.
Henry R. Kranzler, a psychiatrist at the University of Connecticut School of Medicine in Farmington, says the new results herald rapid progress in finding medications that help specific sets of patients with alcoholism.
John S. Searles, a psychologist at the University of Vermont School of Medicine in Burlington, disagrees. He regards ondansetron’s effects on alcohol use as “pretty small and inconclusive” compared with those elicited by group psychotherapy alone. Further research should track patients with early-onset alcoholism who get ondansetron without group psychotherapy, Searles says.
The drug naltrexone, previously reported as promising for treating alcoholism (SN: 11/21/92, p. 341), has yet to make inroads among clinicians.