Methoxypolyethylene Glycol–Epoetin Beta

INTRODUCTION

Indications

Anemia due to chronic renal failure.

Action

Stimulates erythropoiesis (production of red blood cells). Therapeutic Effects: Maintains and may elevate RBCs, decreasing the need for transfusions.

Adverse Reactions/Side Effects

CNS: SEIZURES, headaches. CV: CARDIOVASCULAR AND THROMBOTIC EVENTS, hypertension, hypotension. GI: diarrhea, constipation, vomiting. Hemat: PURE RED APLASIA. Misc: ALLERGIC REACTIONS, INCLUDING ANAPHYLAXIS, fistula complications.

PHYSICAL THERAPY IMPLICATIONS

Examination and Evaluation

• Monitor continually and seek immediate medical assistance if patient develops any of the following signs or syndromes:

  • ∘ Myocardial infarction, as indicated by sudden chest pain, pain radiating into the arm or jaw, shortness of breath, dizziness, sweating, anxiety, and nausea.

  • ∘ Stroke, as indicated by severe headache, confusion, nausea, vomiting, paralysis, numbness, speech problems, and visual disturbances.

  • ∘ Seizures, as indicated by various symptoms depending on the type of seizure such as decreased consciousness, changes in muscle tone, muscle twitches/jerking, convulsions, automatisms (lip smacking, chewing), and strange auditory, visual, and other sensations.

  • ∘ Lack of red blood cells and their precursors (red cell aplasia), as indicated by unusual fatigue, shortness of breath with exertion, pallor, and bruising.

  • ∘ Hypersensitivity reactions and anaphylaxis, including pulmonary symptoms (tightness in the throat and chest, wheezing, cough, dyspnea) or skin reactions (rash, pruritis, urticaria).

• Assess blood pressure (BP) and compare to normal values (See Appendix F). Report changes in BP, either a problematic decrease in BP (hypotension) or a sustained increase in BP (hypertension).

Interventions

• Because of the risk of thrombosis, use caution during aerobic exercise and other forms of therapeutic exercise. Assess exercise tolerance frequently (BP, heart rate, fatigue levels), and terminate exercise immediately if any untoward responses occur (See Appendix L).

• If administered via subcutaneous injection, do not apply massage or physical agents (heat, cold, electrotherapeutic modalities) at or near the application site. These interventions can alter drug absorption from subcutaneous tissues.

Patient/Client-Related Instruction

• Caution patient and family/caregivers about risks of coronary thrombosis, stroke, seizures, anemia, and hypersensitivity reactions. Review warning signs of these problems (see above under Evaluation and Examination), and instruct patient and family/caregivers to report any suspicious symptoms to the physician.

• Instruct patient to report other troublesome side effects such as severe or prolonged headache or GI problems (vomiting, diarrhea, constipation).

Pharmacokinetics

Absorption: Well absorbed (62%) following subcutaneous administration; IV administration results in complete bioavailability.

Distribution: Unknown.

Metabolism and Excretion: Unknown.

Half-life: 134 hr.