Prozac Prevents Bulimia Relapse

Jan. 16, 2002 -- Studies have already shown that the antidepressant fluoxetine, better known by the trade name Prozac, is effective for short-term, emergency treatment of severe bulimia. Now, a new study shows that continued use of the drug can prevent people with bulimia from falling back into the destructive cycle of repeated bingeing and purging.

The researchers first looked at 232 male and female bulimia patients who, on a regular basis, self-induced vomiting to prevent weight gain after episodes of binge eating. They randomly assigned the 150 people who had responded to a preliminary eight-week course of Prozac to either continued Prozac or placebo for 52 more weeks.

If a patient returned to the same frequency of binge/purge episodes they'd experienced before treatment began, and it lasted for two straight weeks, it was considered a relapse.

Interestingly, being depressed -- and about 40% had symptoms of depression -- made no difference to whether a patient responded to treatment with Prozac.

"[Prozac]-treated patients exhibited a longer time to relapse than placebo-treated patients," write study leader Steven J. Romano, MD, and colleagues from 16 U.S. medical centers. Overall, placebo patients relapsed during the first three months, while Prozac patients held out significantly longer. Unfortunately, both groups eventually showed worsening symptoms.

The complete report appears in the January issue of the American Journal of Psychiatry.

According to the researchers, Prozac wasn't merely alleviating any underlying depression in these patients. There's more to it. People with bulimia appear to have an imbalance of, or malfunction in, the brain chemical serotonin. Among its other diverse functions, serotonin helps us recognize when we've had enough to eat. Thus, "a defect in serotonin function may produce impaired recognition of satiety [fullness], thus contributing to binge eating," they write.

"This study demonstrated that continued treatment with fluoxetine in patients who responded to [preliminary] therapy was well tolerated and associated with a significant reduction in the likelihood of relapse during a 52-week monitoring period," the researchers write.

The fact that symptoms gradually worsened for patients in both the Prozac and the placebo groups, however, suggests that a truly effective approach to fighting bulimia will likely include more than just one drug, along with ongoing psychiatric counseling.

Eli Lilly and Company, manufacturer of Prozac and a WebMD sponsor, provided funding for this study.