Eating Disorders
New Treatments for Binge Eating and Bulimia

Epilepsy drugs Topamax and Zonegran show promise

(April 15, 2003) - Specialists in eating disorders are constantly looking for new treatments. So the arrival of two new drugs that appear to curb food cravings and reduce appetite has piqued substantial interest.

In the last few years, psychiatrists have been prescribing Topamax and Zonegran for people whose overeating meets the criteria for binge eating disorder, as well as for those with bulimia, who binge and then vomit, use laxatives or exercise to compensate.

Experts say that the drugs, developed originally for epilepsy, show promise for the eating disorders, but that more research is needed on their effectiveness.

Topamax, which entered the market in 1996, has so far been used more widely than Zonegran, introduced four years later.

Dr. Susan L. McElroy, a psychiatrist at the University of Cincinnati and the lead author of a study of Topamax and binge eating disorder, said the drug "needs to be used carefully, but it clearly has been helpful for a subset of patients with binge eating."

Psychiatrists define the disorder, which afflicts about 2 percent of the population and about 30 percent of Americans treated for obesity, as recurrent episodes of binge eating at least twice a week for at least six months and that cause significant distress.

Unlike college students who occasionally inhale a box of cookies in a study marathon, people who suffer from the disorder routinely consume many thousands of calories at a single sitting. But they do not engage in the "purging" typical of bulimia.

The study, published in February in The American Journal of Psychiatry, found that 94 percent of the patients given Topamax significantly reduced the frequency of their binges, compared with 46 percent of those who received dummy pills. The patients on the drug also lost more weight than the control subjects. The research was financed in part by Ortho-McNeil Pharmaceutical, which makes Topamax.

Dr. McElroy said the drug seemed to restore a sense of satiety after normal eating.

Patients "know that if they start eating they'll be able to stop eating," she said.

But Topamax can also produce side effects, including memory problems, mental fogging, sedation and difficulty concentrating, that prevent a significant number of people from taking the drug. Those side effects, Dr. McElroy and other experts said, can often be minimized or avoided by starting Topamax at very low doses. Topamax and Zonegran should be used with great caution in bulimic patients who are not overweight, the experts said.

A study of bulimia, also financed by the drug company, found that Topamax helped patients cut down on bingeing and vomiting. The study will be presented at a meeting of the American Psychiatric Association in San Francisco next month.

Participants who took the drug reduced the number of days per week that they binged or purged by 44.78 percent, compared with a 10.7 percent reduction among people who took a placebo, said Dr. Scott Hoopes, a psychopharmacologist in Boise, Idaho, and the principal investigator.

Dr. Hoopes said that many patients who craved doughnuts, potato chips and other high-carbohydrate treats before taking Topamax eliminated those cravings with the drug and sometimes even developed an aversion to carbohydrates. One subject, he said, "reported that she had loved Pepsi but couldn't stand it anymore."

Neither Topamax nor Zonegran is specifically approved by the Food and Drug Administration for eating disorders. But once drugs receive approval for one purpose, they can be prescribed for other illnesses.

Even so, Dr. Katherine Halmi, a professor of psychiatry at Weill Medical College of Cornell University, said the drugs should be considered only as "a second or third line of defense," behind other treatments like psychotherapy and antidepressants.

Source: The American Journal of Psychiatry, Feb. 2003

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