Erlotinib

INTRODUCTION

Indications

Locally advanced/metastatic non–small-cell lung cancer which has not responded to previous chemotherapy.

Action

Inhibits the enzyme tyrosine kinase which is associated with human epidermal growth factor receptor (EGFR); blocks growth stimulation signals in cancer cells. Therapeutic Effects: Decreased spread of lung cancer with increased survival.

Adverse Reactions/Side Effects

CNS: fatigue. EENT: conjunctivitis, corneal ulceration. Resp: INTERSTITIAL LUNG DISEASE, dyspnea, cough. GI: diarrhea, abdominal pain, anorexia, nausea, stomatitis, vomiting, ↑ liver transaminases. Derm: rash, dry skin, pruritus.

PHYSICAL THERAPY IMPLICATIONS

Examination and Evaluation

• Assess any breathing problems or signs of interstitial lung disease such as dry cough, wheezing, chest pain, shortness of breath, and difficult or labored breathing. Monitor pulse oximetry and perform pulmonary function tests (See Appendices I, J, K) to quantify suspected changes in ventilation and respiratory function.

• Monitor any vision disturbances or eye pain and inflammation. Report these signs to the physician.

Interventions

• For patients who are medically able to begin exercise, implement appropriate resistive exercises and aerobic training to maintain muscle strength and aerobic capacity during cancer chemotherapy or to help restore function after chemotherapy.

• Use caution during aerobic exercise and endurance conditioning because of potential pulmonary toxicity. Terminate exercise if patient exhibits untoward symptoms (chest pain, shortness of breath, unusual fatigue) or displays other criteria for exercise termination (See Appendix L).

Patient/Client-Related Instruction

• Advise patient and family/caregivers that fatigue and weakness are likely and may be severe. Functional abilities may be limited, and patient may need to use assistive devices during ambulation.

• Advise patient that skin reactions are likely, including rash, dry skin, and pruritus. Report severe or unexpected skin reactions to the physician.

• Advise patient about the likelihood of GI reactions (abdominal pain, diarrhea, nausea, vomiting, loss of appetite, inflammation in/around mouth). Instruct patient to report severe or prolonged GI problems.

Pharmacokinetics

Absorption: 60% absorbed; bioavailability increased to 100% with food.

Distribution: Unknown.

Protein Binding: 93% protein bound.

Metabolism and Excretion: Mostly metabolized by the liver (CYP3A4 enzyme system).

Half-life: 36 hr.

Contraindications/Precautions

Contraindicated in: Pregnancy or lactation.

Use Cautiously in: Hepatic impairment; Previous chemotherapy/radiation, preexisting lung disease, metastatic lung disease (may ↑ risk of interstitial lung disease); Patients with childbearing potential; Children (safety not established).