To determine whether fluoxetine is effective in the long-term treatment of obesity and whether it is particularly useful in the treatment of obese binge-eaters, the authors randomly assigned 45 obese subjects (22 with binge-eating problems and 23 without binge-eating) to fluoxetine (60 mg/day) or placebo in a 52-week double-blind trial. The 21 subjects who completed the trial made 13 clinic visits and were taught basic behavior modification strategies. Patients treated with fluoxetine plus behavior modification lost significantly more weight than those treated with placebo plus behavior modification. However, the drug did not appear to have a differential benefit for binge-eaters.