Azithromycin (Zithromax) is a macrolide antibiotic that works as a bacteriostatic or bactericidal in susceptible bacteria.

Drug Class

Macrolide antibiotic

Therapeutic Actions

Bacteriostatic or bactericidal in susceptible bacteria.

Indications

• Treatment of LRIs(Lower Respiratory Infections): Acute bacterial exacerbations of COPD due to H. influenzae, Moraxella catarrhalis, S. pneumoniae; community-acquired pneumonia due to S. pneumoniae, H. influenzae
• Treatment of LRIs: Streptococcal pharyngitis and tonsillitis due to Streptococcus pyogenes in those who cannot take penicillins
• Treatment of uncomplicated skin infections due to Staphylococcus aureus, S. pyogenes, Streptococcus agalactiae
• Treatment of nongonococcal urethritis and cervicitis due to C. trachomatis; treatment of PID
• Treatment of acute sinusitis
• Treatment of otitis media caused by H. influenzae, M. catarrhalis, S. pneumoniae in children > 6 mo
• Treatment of pharyngitis and tonsillitis in children > 2 yr who cannot use first-line therapy
• Prevention and treatment of disseminated Mycobacterium avium complex (MAC) in patients with advanced AIDS
• Unlabeled uses: Uncomplicated gonococcal infections caused by N. gonorrhoeae; gonococcal pharyngitis caused by N. gonorrhoeae; chlamydial infections caused by C. trachomatis; prophylaxis after a sexual attack.

Contraindications and cautions

• Contraindicated with hypersensitivity to azithromycin, erythromycin, or any macrolide antibiotic.
• Use cautiously with gonorrhea or syphilis, pseudomembranous colitis, hepatic or renal impairment, lactation.

Available forms

Tablets—250, 600 mg; powder for injection—500 mg; powder for oral suspension—100 mg/5 mL, 200 mg/5 mL, 1 g/packet

Dosages

ADULTS

• Mild to moderate acute bacterial exacerbations of COPD, pneumonia, pharyngitis, and tonsillitis (as second-line): 500 mg PO single dose on the first day, followed by 250 mg PO daily on days 2–5 for a total dose of 1.5 g or 500 mg/day PO for 3 days.
• Nongonococcal urethritis and cervicitis due to C. trachomati: A single 1-g PO dose.
• Gonococcal urethritis and cervicitis: A single dose of 2 g PO.
• Disseminated MAC infections: For prevention, 1,200 mg PO taken once weekly. For treatment, 600 mg/day PO with etambutol.
• Acute sinusitis: 500 mg/day PO for 3 days.

PEDIATRIC PATIENTS

• Otitis media: Initially, 10 mg/kg PO as a single dose, then 5 mg/kg on days 2–5 or 30 mg/kg PO as a single dose.
• Community-acquired pneumonia: 10 mg/kg PO as a single dose on first day, then 5 mg/kg PO on days 2–5.
• Pharyngitis or tonsillitis: 12 mg/kg/day PO on days 1–5.
• Acute sinusitis: 10 mg/kg/day PO for 3 days.

Adverse effects

• CNS: Dizziness, headache, vertigo, somnolence, fatigue
• GI: Diarrhea, abdominal pain, nausea, dyspepsia, flatulence, vomiting, melena, pseudomembranous colitis
• Other: Superinfections, angioedema, rash, photosensitivity, vaginitis

Patient education

• Take the full course prescribed. Do not take with antacids. Take with food if GI upset occurs.
• You may experience these side effects: Stomach cramping, discomfort, diarrhea; fatigue, headache (medication may help); additional infections in the mouth or vagina (consult with a health care provider for treatment).
• Report severe or watery diarrhoea, severe nausea or vomiting, rash or itching, mouth sores, vaginal sores.
• Educate patient to take the drug on an empty stomach 1 hr before or 2–3 hr after meals. Food affects the absorption of this drug.