A number of compounds having an effect on serotonergic transmission have been shown to have a beneficial therapeutic action in patients with bulimia nervosa. Many previous studies, however, have suffered from methodological shortcomings, in particular small population sizes. This article reviews present data which suggest that fluoxetine is effective in the treatment of bulimia nervosa. Two trials of unprecedented size (n = 387 and 398, respectively) have recently been reported. These two studies show that fluoxetine, 60 mg daily, has a clear beneficial effect on behavioural and other (attitudinal) measures of bulimic symptomatology, and that this dose of fluoxetine is well tolerated in patients with bulimia nervosa. The role of pharmacotherapy in the long-term treatment of this disorder and the relative roles of pharmacotherapy and psychotherapy in treating bulimia nervosa are also discussed.