Mecasermin

INTRODUCTION

Indications

Long-term treatment of growth failure in children due to primary insulin-like growth factor-1 (IGF) deficiency or growth hormone gene deletion with antibodies to growth hormone.

Action

Under normal conditions, growth hormone attaches to receptors resulting in increased production of IGF-1. IGF-1 stimulates uptake of glucose, fatty acids, and amino acids which support tissue growth. These processes signal and support statural growth. Therapeutic Effects: Replacement of IGF-1 in deficiency states resulting in achievement of optimal potential statural growth.

Adverse Reactions/Side Effects

CNS: SEIZURES, dizziness, headache, intracranial hypertension. Resp: tonsillar hypertrophy, snoring. GI: vomiting. Endo: HYPOGLYCEMIA. Local: bruising, lipohypertrophy. MS: arthralgia, extremity pain. Misc: thymus hypertrophy.

PHYSICAL THERAPY IMPLICATIONS

Examination and Evaluation

• Be alert for new seizures or increased seizure activity, especially at the onset of drug treatment. Document the number, duration, and severity of seizures, and report these findings to the physician immediately.

• Monitor signs of hypoglycemia, especially during and after exercise. Common neuromuscular symptoms include anxiety; restlessness; tingling in hands, feet, lips, or tongue; chills; cold sweats; confusion; difficulty in concentration; drowsiness; nightmares or trouble sleeping; excessive hunger; headache; irritability; nervousness; tremor; weakness; and unsteady gait. Report repeated or severe episodes of hypoglycemia to the physician.

• Periodically assess height and weight in children to help document the effects of drug therapy.

• Be alert for signs of intracranial hypertension, including headache, dizziness, ringing in the ears, nausea, vomiting, pain in the neck/back/shoulders, and vision disturbances (blurred vision, double vision, flashes of light, brief periods of blindness). Notify physician of these signs immediately.

• Assess any joint pain or extremity pain to rule out musculoskeletal pathology; that is, try to determine if pain is drug induced rather than caused by anatomic or biomechanical problems.

• Monitor subcutaneous injection site for bruising or increased fat accumulation (lipohypertrophy). Report prolonged or excessive injection site reactions to the physician.

Interventions

• Design and implement therapeutic exercise programs to capitalize on growth hormone effects and increase muscle strength and function in children.

• Do not apply physical agents (heat, cold, electrotherapeutic modalities) or massage over the injection site; these interventions can alter drug absorption from subcutaneous tissues.

• Provide a source of oral glucose (fruit juice, glucose gels/tablets, etc.) to treat mild hypoglycemia. Call for emergency assistance if symptoms persist or in cases of severe hypoglycemia. Emergency treatment typically consists of IV glucose, glucagon, or epinephrine.

Patient/Client-Related Instruction

• Instruct patient to report other bothersome side effects such as severe or prolonged headache, dizziness, vomiting, or problems related to tonsillar hypertrophy (snoring, difficulty breathing).

Pharmacokinetics

Absorption:...