COLORADO SPRINGS — By far, the most effective weight-loss medication on the market is one that isn't even approved for that indication, Dan Bessesen, M.D., said at a meeting of the Colorado Chapter of the American College of Physicians.
Topiramate (Topamax) is approved by the Food and Drug Administration for treating epilepsy and for migraine prophylaxis. It also causes as a “side effect”—a 10%-13% weight loss. Nothing comparable in terms of efficacy has been seen since the phentermine/fenfluramine combination (phen-fen) that was ultimately derailed by a blizzard of lawsuits due to safety issues. By comparison, the various approved weight-loss drugs provide a modest 5%-8% weight loss. But topiramate also has unwelcome neurocognitive side effects, said Dr. Bessesen, head of the section of endocrinology at Denver Health Medical Center.
Another drug that causes weight loss as a side effect is the antidepressant bupropion (Wellbutrin). In one large double-blind trial in obese patients, 300 mg/day of bupropion SR produced a placebo-subtracted 2.2% net weight loss at 24 weeks, while 400 mg/day yielded a 5.1% loss (Obes. Res. 2002;10:633-41).