Treatment of anorexia and weight loss with megestrol acetate in patients with cancer or acquired immunodeficiency syndrome.

Anorexia is a symptom of cancer and a cause of decreased caloric intake and weight loss. Successful treatment for anorexia can improve the patient's well-being and prevent or reverse the effects of anorexia on nutrition. Following reports of appetite enhancement and weight gain in uncontrolled studies of high-dose (320 to 1,600 mg/d) megestrol acetate in patients with cancer or AIDS (acquired immunodeficiency syndrome), several randomized, placebo-controlled trials have been completed. These trials demonstrate that megestrol acetate therapy improves appetite and food intake in patients with anorexia and advanced cancer, leading to weight gain in a subset of patients. The mechanisms of action of megestrol acetate (a progesterone derivative) probably include both behavioral and metabolic effects. Several carefully designed randomized trials are under way to establish the optimal dose and to determine the mechanism of weight gain. Patients with cancer or AIDS who complain of anorexia and whose nutritional status is compromised may benefit from megestrol acetate therapy.