Epilepsy Drug May Also Be Magic Weight-Loss Bullet

There may be a promising new entry in the high-stakes, high-profit search for a weight-loss pill. It's a drug already used for a whole different purpose, as medical correspondent Elizabeth Kaledin reports.

The drug is called Topamax: It's been on the market since 1997 to treat epileptic seizures. But now it seems this little-known pill has a side effect that's causing a stir: Patients who take it lose weight.

"The magnitude ranged from 6 to 8 pounds to a 100 pounds in some patients," says Dr. Victor Biton, director of the Arkansas Epilepsy Program.

Biton was a lead investigator in early trials of the drug and now prescribes it widely to treat epilepsy in his own practice:

"In my patient population I would estimate that half of my patients lost more than 10% of their baseline body weight," says Biton.

Obesity experts following the drug's history say it's premature to call it a magic pill. It's still unclear what's causing the weight loss, but most people who take it simply report a loss of appetite.

Right now Topamax is approved by the FDA only as an antiseizure drug, but Johnson & Johnson, its manufacturer, is conducting several trials to test its safety in overweight people who don't have epilepsy.

In small doses it has few negative side effects, but there is concern that in the higher doses needed for large-scale weight loss, Topamax may cause memory loss and slowing of mental functions.

"It's pretty safe and it's pretty effective and if it can help the problem of weight gain it would be beneficial to everyone involved," says Biton.

It would be especially beneficial to Johnson & Johnson. With obesity now labeled the public health crisis of the 21st century, the drug maker has a lot to gain by developing a pill that could help people lose.
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