Anti-Nausea Drug Helps Bulimics

March 2, 2000 (Atlanta) -- A drug used to lessen the side effects of chemotherapy for cancer patients seems to help bulimic women reduce -- or even stop -- their cycle of binge eating and purging. Results of a small study reported Thursday indicate that the anti-nausea drug Zofran can reduce by half the number of binge/purge episodes in bulimic patients.

A larger study, which is now enrolling patients, must be completed before researchers can confirm whether the results are scientifically valid. But one of the 26 study participants says she doesn't need further proof.

"Within two days of taking the medicine, the symptoms disappeared -- after 12 years," the 27-year-old woman, who identified herself only as Cheryl, tells WebMD. "I did not have a reduction in symptoms; I had complete remission."

Study author Patricia L. Faris, PhD, stresses that Zofran (ondansetron) is no cure for bulimia. "I think it would be unconscionable to give the opinion that patients could come to our office and be cured," she tells WebMD. "I think what patients should be able to expect is several things. Maybe a restoration of their own self-respect: They don't have this problem because they are weak, but because they have a real physiological problem. They should also be able to expect help. With the watchful eye of a helpful physician, this is a viable treatment option."

Bulimia, like its sister eating disorder anorexia, involves a pervasive fear of weight gain. Bulimic patients, who are almost always female, develop a pattern of binge eating followed by self-induced vomiting. In the severe form of this disorder, bulimic patients binge and purge at least seven times each week. Currently, the best treatment is psychotherapy -- particularly a form known as cognitive-behavioral therapy, which seeks to normalize patients' eating habits and reduce their emphasis on weight. Antidepressant medications, such as Prozac (fluoxetine), also prove helpful.

The new study, the culmination of 10 years of work at the University of Minnesota, is based on a completely new theory about bulimia. Faris and colleagues suggest that constant bingeing and purging actually damages an important nerve -- the vagus, which controls the sensation of feeling full after eating.

"The disease starts off voluntarily," Faris says. "The women think, 'I can engage in binge eating and get away with it', but every time they vomit, that is a real jolt to the vagus, and the vagus gets used to this really intense stimulation. It then begins to cycle in patterns of increased activity. When activity in the vagus nerve becomes hyperactive, that is interpreted as the urge to engage in bulimic behaviors. A vicious cycle happens. You start out having ... control over it, but over time your binge frequency increases."

A commentary published with the study notes that there is no real way to prove this theory. But Angela S. Guarda, MD, director of the Johns Hopkins eating-disorder program, tells WebMD that the basic hypothesis appears sound. "I don't think it's totally off the wall," says Guarda, who was not involved in the study. "It is possible. Engaging in the behavior does create a physiological change that sustains the behavior."

Cheryl says that is exactly how it feels to her. Previous psychotherapy had helped her overcome her distorted body image, but the compulsion to binge and purge remained. "It's not something that originated in my head; it was something visceral -- like a primal need," she says. "It had nothing to do with taste or what I wanted to eat."

Theorizing that Zofran would act to calm the overexcited nerves, Faris and co-workers used the drug to treat a few bulimic patients. It seemed to help, so they went on to conduct the study with severely bulimic women, who did not receive any other form of treatment during the six-week study period. On average, participants who received Zofran reduced the number of binge/purge episodes from more than 13 episodes per week to 6.5 episodes. No such reduction was seen in participants who got pills that did not contain the drug.

Would this kind of reduction mean anything to a patient? Cheryl says it would. "The time spent in the cycle consumes your life," she says. "To go from 14 to seven episodes saves people a lot of time; it gives them back their life. I went from seven to none. But even if I had gone from 10 to two, I would have been happy enough to save 30 hours of my life a week."

The speed of the reduction in binge/purge episodes with Zofran is remarkable, but Bruce A. Arnow, PhD, who was not connected with the study, tells WebMD that psychotherapy can reduce bulimic behavior even more. "Cognitive-behavioral therapy has substantially higher reductions in purging episodes, 70-90%," says Arnow, chief of Stanford University's behavioral psychiatry section. "Abstinence rates -- people who flat-out stop -- are between 30% and 50%. These benefits appear to be reasonably well maintained and are also associated with reduced [accompanying] symptoms such as depression."

Faris agrees that psychotherapy is an integral component of treatment for bulimia. In the expanded clinical trial for which she is now recruiting patients, only half the participants will receive Zofran, but all will receive psychotherapy. She suggests that the physicians of patients who are not responding to other treatments might want to try a short-term trial of the drug.

The main side effect of Zofran is constipation, which Cheryl describes as "terrible." But she carries the drug with her in case the craving to binge and purge comes back, as it did recently after three years of remission. "You live your life in a haze when you have this craving," she says. "With the drug, it is like seeing clearly again."