Iron, incorporated into the heme porphyrin ring, is an essential component of normal erythropoiesis. Intravenous (IV) iron supplementation has become standard practice to treat iron deficiency anemia for patients receiving dialysis. During the last decade, the percentage of patients in US-based dialysis centers receiving IV iron in a given month has increased from ∼50% to>70%,1 driven by a combination of changes in dialysis reimbursement,2 improved hypersensitivity profiles of IV iron formulations,3 and concerns about the safety of erythropoiesis-stimulating agents (ESAs).