Dirithromycin

INTRODUCTION

Indications

Treatment of the following infections: Acute bacterial exacerbations of chronic bronchitis due to Haemophilus influenzae, Moraxella catarrhalis, or Streptococcus pneumoniae, Secondary bacterial infections of acute bronchitis due to M. catarrhalis or S. pneumoniae, Community-acquired pneumonia due to Legionella pneumophila, Mycoplasma pneumoniae, or S. pneumoniae, Pharyngitis/tonsillitis due to S. pyogenes, Uncomplicated skin/skin structure infections due to methicillin-susceptible strains of Staphylococcus aureus or S. pyogenes.

Action

Suppresses protein synthesis at the level of the 50S bacterial ribosome. Therapeutic Effects: Bacteriostatic action against susceptible bacteria. Spectrum: Active against gram-positive aerobes, including S. aureus (methicillin-susceptible), S. pneumoniae, and S. pyogenes. Active against gram-negative aerobes, including H. influenzae, L. pneumophila, M. catarrhalis. Also active against M. pneumoniae.

Adverse Reactions/Side Effects

CNS: dizziness/vertigo, headache, insomnia, weakness. Resp: dyspnea, increased cough. GI: PSEUDOMEMBRANOUS COLITIS, abdominal pain, diarrhea, dyspepsia, flatulence, nausea, vomiting. GU: vaginitis. Derm: pruritus/urticaria, rash.

PHYSICAL THERAPY IMPLICATIONS

Examination and Evaluation

• Monitor signs of pseudomembranous colitis, including diarrhea, abdominal pain, fever, pus or mucus in stools, and other severe or prolonged GI problems (nausea, vomiting, heartburn). Notify physician or nursing staff of these signs immediately.

• Assess any breathing problems, and report increased cough or difficult, labored breathing.

• Assess dizziness and vertigo 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.

Interventions

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

Patient/Client-related Instruction

• Instruct patient to report other troublesome side effects such as severe or prolonged headache, sleep loss, vaginal irritation, skin reactions (rash, itching, hives), or GI problems (diarrhea, nausea, vomiting, indigestion, abdominal pain).

Pharmacokinetics

Absorption: Dirithromycin is a prodrug. It is converted to erythromycylamine, the active compound, during intestinal absorption, resulting in bioavailability of 10%.

Distribution: Erythromycylamine—rapidly and widely distributed, resulting in high tissue concentrations.

Metabolism and Excretion: Erythromycylamine—81–97% eliminated in bile (fecal/hepatic route); 2% eliminated in urine.

Half-life: Erythromycylamine—2–36 hr.

Contraindications/Precautions

Contraindicated in: Hypersensitivity to dirithromycin, erythromycin, or other macrolide anti-infectives; Known, suspected, or potential bacteremia (serum levels are ...