Objective: To examine the effect of megestrol acetate on nutritional parameters in a hemodialysis population. Design: Prospective case studies of hemodialysis patients. Setting: A freestanding, nonprofit, hemodialysis unit. Subjects: Seventeen patients were studied. They were included regardless of gender, age, or cause of renal disease. They had to be on dialysis for at least 2 months, had a serum albumin <3.5 g/dL for these 2 months, and had to be at high nutritional risk. There were 8 women and 9 men. Ages were 44 to 87 years. Eight were diabetics, and 9 were nondiabetics. Interventions: Megestrol acetate 400 mg orally twice daily was prescribed, and patients were studied for 6 months. Outcome measures: Pre-evaluation and postevaluation were performed by patient questionnaire, Subjective Global Assessment (SGA), dry weight, and anthropometric measurements. Monthly laboratory monitoring included albumin, prealbumin, blood urea nitrogen (BUN), cholesterol, triglycerides, carbon dioxide, platelets, hematocrit, alanine aminotransferase (ALT), aspartate aminotransferase (AST), gammaglutamyl transpeptidase (GGT), lactate dehydrogenase (LDH), alkaline phosphatase, and glucose. Glycohemoglobin and hemoglobin A1c were monitored in diabetic patients. Results: Three patients were able to take megestrol acetate for 5 to 6 months. They reported improved appetite and showed an increase in dry weight. The annualized mortality rate was about 59%. Side effects included diarrhea, confusion, hyperglycemia, headaches, dizziness, and elevated LDH. Conclusion: Megestrol acetate may help stimulate appetite in the hemodialysis patient, but it is risky and must be monitored closely. Eight hundred milligrams per day is probably too large a dose for the end-stage renal disease (ESRD) patient.