Erythropoietin (EPO), also known as erythrocyte stimulating factor or erythropoietin, is an endogenous glycoprotein hormone in the human body that can stimulate the production of red blood cells. Hypoxia can stimulate the production of erythropoietin. Recombinant human erythropoietin has long been used in clinical practice to treat anemia associated with renal insufficiency, anemia caused by acquired immunodeficiency syndrome/AIDS itself or treatment, anemia associated with malignant tumors, and anemia caused by rheumatic diseases.