Administration of erythropoietin should be limited to patients with renal anemia who are causing inconvenience in daily lives by being accompanied during anemia. Moreover, erythropoietin should be intended for patients with less than 10g/dl of hemoglobin (30% as hematocrit) in case of renal anemia.
Erythropoietin should not be administered to the other anemia.
Sufficient examination by asking should be made to estimate responses. Moreover, in case administration is initiated or the first dose after discontinuation is administered, it is desirable that total volume be administered after confirming that abnormal response would not occur, by injecting little amount of erythropoietin into vein.
During therapy, hemoglobin and hematocrit should be regularly monitored (about once a week in the early phase of administration, once per every other week in the maintenance phase) with sufficient care to avoid exceeding target range of hematopoiesis (≥12g/dl as hemoglobin or ≥36% as hematocrit). If it is recognized hematopoiesis required is exceeded, appropriate treatments including discontinuance of administration should be made.
Since rise in blood pressure and hypertensive encephalopathy may occur, blood pressure and hematocrit should be increased slowly. Also, hematocrit may increase even after administration is discontinued, and sufficient monitoring should be made. Therefore, blood pressure in patients treated with erythropoietin, particularly patients with cardiovascular disease or patients with chance of hypertension should be carefully monitored. As in case of patients with rapid increase in hematocrit (increases by more than 4% in a 2-week period), excessive rise in hematocrit may exacerbate hypertension, dose should be adjusted.
Among patients with chronic renal failure (CRF) involved in clinical trials of erythropoietin, seizures have been observed. Higher rate of seizures (about 2.5% of patients) appeared in patients on dialysis during the first 90 days of therapy than later time period. In double-blind, placebo-controlled trials involving cancer patients on chemotherapy, seizures were reported in 3.2% (N = 2/63) of patients treated with erythropoietin and 2.9% (N = 2/68) of patients treated with placebo. However, both patients treated with erythropoietin had underlying CNS disease which might have been related to seizures. Therefore, blood pressure and previously known neurologic symptoms should be closely monitored in patients treated with erythropoietin.
Since the thrombotic events such as myocardial infarction, pulmonary embolism, cerebrovascular accident, or transient ischemic attack were observed during erythropoietin therapy, the patients with vascular disease should be carefully monitored.
Since hyperkalemia may be caused by erythropoietin administration, proper dietary management should be carried out.
Since iron is important to erythropoietin therapy, in case of iron deficiency, iron should be supplemented.
Erythropoietin is primarily a growth factor of erythropoiesis. However, the possibility that erythropoietin may act as a growth factor of tumor type, particularly such as myeloid malignancies cannot be excluded.
Incidence of pure red cell anemia (PRCA) has been rarely reported among CRF patients with administration of erythropoietin preparation from months to years. Since most cases of PRCA were found after administration of erythropoietin preparation via s.c. injection, The i.v. route is recommended for the injection of this product. Anti-erythropoietin antibody was found in most cases of PRCA patients. In cases of unexpected diminish of effect, the patients should be checked for the typical causes of non-response to this preparation such as iron, folic acid, or vitamin B12 deficiency, aluminum storage disease, infection or inflammation, exsanguinations, and hematolysis. For the case of PRCA with unknown causes, inspection of marrow should be considered. Diagnosis of PRCA should be followed by checking the presence of anti-erythropoietin antibody and discontinue of administration of this preparation. Since antibodies against erythropoietin preparation show cross-reactivity to other erythropoietin preparations, any erythropoietin preparations should not be used. Other causes of PRCA should be checked for adequate treatments.