Oxymetholone (17beta-hydroxy-2-[hydroxymethylene]-17-methyl-5alpha-androstan-3-one) is a 17alpha-alkylated anabolic-androgenic steroid and a synthetic derivative of testosterone. It has been approved by the US Food and Drug Administration for the treatment of anemias caused by deficient red cell production. Acquired aplastic anemia, congenital aplastic anemia, myelofibrosis and the hypoplastic anemias due to the administration of myelotoxic drugs often respond. Drug interactions exist with cimetidine, paroxetine, and haloperidol, but are not expected with indinavir, ritonavir, clarithromycin, or itraconazole.