Seven patients with sickle cell anemia were treated with oxymetholone for at least 2 mo. Markedly increased basal rates of hemolysis and erythropoiesis were confirmed. The urinary erythropoietin excretion was either normal or lower than expected for the red cell mass, and an expanded blood volume was due primarily to an increased plasma volume. After androgen therapy, six patients demonstrated more than a fivefold increase in urinary erythropoietin, with an increase in red cell mass ranging from 17%-75% above the control value. All showed a decline in serum iron level to the 25-75 mug/100 ml range within 4 wk after the start of therapy. Less marked changes followed lower oxymetholone doses. Reversible hepatic toxicity, with a serum bilirubin concentration exceeding 50 mg/100 ml, occurred in one patient. Androgenic hormone therapy may be useful for selected adult patients with sickle cell disease when severe anemia contributes to disease morbidity.