People with kidney failure are at risk for the development of anemia. Anemia is a decrease in the production of hemoglobin, a substance that carries oxygen in the blood. The majority of patients require erythropoietin and iron supplementation to correct the anemia. In some patients, the hemoglobin fails to rise to a desired level despite treatment with erythropoietin and iron. There have been several studies in hemodialysis patients showing that vitamin C given intravenously helps to correct anemia in patients already on erythropoietin and iron.