Oral Nifedipine to Treat Iron Overload

Iron overload is common worldwide. If left untreated, body iron overload leads to multiple organ abnormalities including hepatic, endocrine (diabetes) and cardiac failure. In patients with ineffective erythropoiesis, iron overload results from the combination of increased intestinal absorption and transfusion. Unfortunately, physiological means to remove excess iron are limited, and treatments are limited to therapeutic phlebotomy and chelation therapy. While phlebotomy is the preferred therapy for patients with hemochromatosis, therapy for anemic patients is largely limited to chelation drugs. Since those drugs are frequently inadequate, additional iron-reduction therapies are being sought. Based upon recently published data in a rodent model, the purpose of this study is to determine if nifedipine will increase iron excretion in the urine among humans with increased levels of iron. Volunteers will be given a single oral dose (20mg) of nifedipine. Iron level in collections of urine will be measured and compared before and after nifedipine to determine if there is an associated increase in urinary iron excretion.