EPOETIN ALFA (HUMAN RECOMBINANT ERYTHROPOIETIN)

(e-po-e-tin)

Epogen, Eprex

, Procrit
Classifications: blood former; hematopoietic growth factor;
Therapeutic: antianemic; human erythropoietin
Pregnancy Category: C

Availability

2000 units/mL, 3000 units/mL, 4000 units/mL, 10,000 units/mL, 20,000 units/mL

Action

Human erythropoietin is produced in the kidney and stimulates bone marrow production of RBCs (erythropoiesis). Hypoxia and anemia generally increase the production of erythropoietin. Epoetin alpha is a glycoprotein that stimulates RBC production.

Therapeutic Effect

Stimulates the production of RBCs in the bone marrow of severely anemic patients.

Uses

Elevates the hematocrit of patients with anemia secondary to chronic kidney failure (CRF); patients may or may not be on dialysis; other anemias related to malignancies and AIDS. Autologous blood donations for anticipated transfusions. Reduces need for blood in anemic surgical patients.

Contraindications

Uncontrolled hypertension and known hypersensitivity to mammalian cell–derived products and albumin (human); hamster protein hypersensitivity; iron-deficiency anemia, pregnancy (category C); lactation; neonates.

Cautious Use

Leukemia, sickle cell disease; coagulopathy; seizure disorders.

Route & Dosage

Anemia
Adult: SC/IV Start with 50–100 U/kg/dose until target Hct range of 30–33% (max: 36%) is reached, Hct should not increase by more than 4 points in any 2-wk period, rapid increase in Hct increases the risk of serious adverse reactions (hypertension, seizures), may increase dose if Hct has not increased 5–6 points after 8 wk of therapy, reduce dose after target range is reached or the Hct increases by >4 points in any 2-wk period, dose usually increased or decreased by 25 U/kg increments
Child: SC/IV 50 U/kg/dose 3 times/wk initially, when Hct increased to 35%, decrease dose by 25 U/kg/dose until Hct reaches 40%

Administration

Subcutaneous

Do not shake solution. Shaking may denature the glycoprotein, rendering it biologically inactive.
Inspect solution for particulate matter prior to use. Do not use if solution is discolored or if it contains particulate matter.
Use only one dose per vial, and do not reenter vial.
Do not give with any other drug solution.

Intravenous

PREPARE: Direct: Give undiluted.

ADMINISTER: Direct: Give direct IV as a bolus dose over 1 min.

Discard any unused portion of the vial. It contains no preservatives.
Store at 2°–8° C (36°–46° F). Do not freeze or shake.

Adverse Effects (≥1%)

CNS: Seizures, headache. CV: Hypertension. GI: Nausea, diarrhea. Hematologic: Iron deficiency, thrombocytosis, pure red cell aplasia, clotting of AV fistula. Other: Sweating, bone pain, arthralgias.

Interactions

Drug: No clinically significant interactions established.

Pharmacokinetics

Onset: 7–14 d. Metabolism: In serum. Elimination: Minimal recovery in urine. Half-Life: 4–13 h.

Nursing Implications

Assessment & Drug Effects

Control BP adequately prior to initiation of therapy and closely monitor and control during therapy. Hypertension is an adverse effect that must be controlled.
Be aware that BP may rise during early therapy as the Hct increases. Notify physician of a rapid rise in Hct (>4 points in 2 wk). Dosage will need to be reduced because of risk of serious hypertension.
Monitor for hypertensive encephalopathy in patients with CRF during period of increasing Hct.
Monitor for premonitory neurological symptoms (i.e., aura, and report their appearance promptly). The potential for seizures exists during periods of rapid Hct increase (>4 points in 2 wk).
Monitor closely for thrombotic events (e.g., MI, CVA, TIA), especially for patients with CRF.
Lab tests: Baseline transferrin and serum ferritin. Monitor aPTT & INR closely. Patients may require additional heparin during dialysis to prevent clotting of the vascular access or artificial kidney. Determine Hct twice weekly until it is stabilized in the target range (30–33%) and the maintenance dose of epoetin alfa has been determined; then monitor at regular intervals. Perform CBC with differential and platelet count regularly. Monitor BUN, creatinine, phosphorus, and potassium regularly.

Patient & Family Education

Important to comply with antihypertensive medication and dietary restrictions.
Do not drive or engage in other potentially hazardous activity during the first 90 d of therapy because of possible seizure activity.
Note: As Hct increases, there is an improved sense of well-being and quality of life. It is important to continue compliance with dietary and dialysis prescriptions.
Understand that headache is a common adverse effect. Report if severe or persistent, may indicate developing hypertension.
Keep all follow-up appointments.

Common adverse effects in italic, life-threatening effects underlined; generic names in bold; classifications in SMALL CAPS; Canadian drug name; Prototype drug

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