Erythropoietin is a protein made mainly in the kidneys that stimulates the bone marrow to produce new red blood cells. Synthetic (man-made) erythropoietin may be used during cancer treatment to prevent anemia or to treat anemia caused by chemotherapy or bone marrow transplant.

Erythropoietin also can be used to treat anemia caused by chronic kidney disease and kidney failure. It elevates or maintains the red blood cell level, decreasing the need for blood transfusions.