Ethambutol

INTRODUCTION

Indications

Active tuberculosis or other mycobacterial diseases (with at least 1 other drug).

Action

Inhibits the growth of mycobacteria. Therapeutic Effects: Tuberculostatic effect against susceptible organisms.

Adverse Reactions/Side Effects

CNS: confusion, dizziness, hallucinations, headache, malaise. EENT: optic neuritis. GI: HEPATITIS, abdominal pain, anorexia, nausea, vomiting. Metab: hyperuricemia. MS: joint pain. Neuro: peripheral neuritis. Misc: anaphylactoid reactions, fever.

PHYSICAL THERAPY IMPLICATIONS

Examination and Evaluation

• Be alert for signs of hepatitis, including anorexia, abdominal pain, severe nausea and vomiting, yellow skin or eyes, fever, sore throat, malaise, weakness, facial edema, lethargy, and unusual bleeding or bruising. Report these signs to the physician immediately.

• Monitor signs of agranulocytosis (fever, sore throat, mucosal lesions, signs of infection), methemoglobinemia (bluish coloring of skin, headache, shortness of breath, lack of energy), or other unusual weakness and fatigue that might be due to other anemias and blood dyscrasias. Report these signs to the physician immediately.

• Monitor signs of hypersensitivity or anaphylactoid reactions, including pulmonary symptoms (tightness in the throat and chest, wheezing, cough, dyspnea) or skin reactions (rash, pruritus, urticaria). Notify physician or nursing staff immediately if these reactions occur.

• Monitor signs of peripheral neuritis (numbness, tingling). Perform objective tests (nerve conduction, monofilaments) to document any neuropathic changes.

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

• Assess dizziness that might affect gait, balance, and other functional activities (See Appendix C). Report balance problems and functional limitations to the physician and nursing staff, and caution the patient and family/caregivers to guard against falls and trauma.

• Be alert for confusion, hallucinations, or other alterations in mental status. Notify the physician promptly if these symptoms develop.

Interventions

• Always wash hands thoroughly and disinfect equipment (whirlpools, electrotherapeutic devices, treatment tables, and so forth) to help prevent the spread of infection. Use universal precautions or isolation procedures as indicated for specific patients.

Patient/Client-Related Instruction

• Instruct patient to report any vision disturbances or eye pain and inflammation that might indicate optic neuritis.

• Instruct patient and family/caregivers to report other troublesome side effects such as severe or prolonged headache, fever, or GI problems (nausea, vomiting, loss of appetite, abdominal pain).

Pharmacokinetics

Absorption: Rapidly and well absorbed (80%) from the GI tract.

Distribution: Widely distributed; crosses blood-brain barrier in small amounts; crosses placenta and enters breast milk.

Metabolism and Excretion: 50% metabolized by the live; 50% eliminated unchanged by the kidneys.

Half-life: 3.3 hr ...