Study Suggests Anti-Nausea Drug May Treat Bulimia

Ondansetron, marketed for the prevention of nausea and vomiting caused by cancer chemotherapy, may be useful in the treatment of bulimia nervosa, concluded Dr. Patricia L. Faris and colleagues from the University of Minneapolis Medical School. The drug blocks the activation of serotonin receptors on afferent vagal nerves in the gastric mucosa, which in turn reduces nausea and vomiting. The researchers suggested that the repeated vomiting characteristic of bulimia causes hyperactivity in the afferent vagal nerve circuits, which also control feelings of satiety. Using ondansetron to decrease this activity could have the effect of reducing bulimic episodes, the researchers hypothesized.

The March 4, 2000, issue of The Lancet describes the small study in which 26 patients with severe bulimia nervosa, defined as at least seven coupled binge/vomit episodes per week, were given either a placebo or ondansetron. The results indicated a significant improvement in the odansetron group in comparison to the placebo group. During the last phase of the study, the binge/vomit episodes averaged 13.2 per week in the placebo group versus 6.5 per week in the active drug group. The odansetron group also demonstrated significant improvement in the number of normal meals and snacks eaten and a decrease in the amount of time spent engaged in bulimic behaviors.

Based on these results, the researchers suggested that odansetron may be a useful treatment for reducing binge/vomit episodes and may help to re-establish normal satiety and meal patterns. However, many questions remain about odansetron as a possible treatment method for bulimia. The safety of long-term odansetron use has not been established. It does not improve other bulimic symptoms, such as poor body image or depression. In addition, the use of odansetron with certain anti-depressant medications may actually hinder the treatment of depression. The small size of the study and the remaining unanswered questions demonstrate the need for further research before odansetron is recommended for the treatment of bulimia.