Pronunciation:
aye-zith-roe-mye-sin
Trade Name(s)
Ther. Class.
agents for atypical mycobacterium
anti-infectives
Pharm. Class.
macrolides
Treatment of the following infections due to susceptible organisms:
Unlabeled Use(s):
Inhibits protein synthesis at the level of the 50S bacterial ribosome.
Therapeutic Effect(s):
Bacteriostatic action against susceptible bacteria.
Spectrum:
Active against the following gram-positive aerobic bacteria:
Active against these gram-negative aerobic bacteria:
Also active against:
Absorption: Rapidly absorbed (40%) after oral administration. IV administration results in complete bioavailability.
Distribution: Widely distributed to body tissues and fluids. Intracellular and tissue levels exceed those in serum; low CSF levels.
Protein Binding: 7–51%.
Metabolism and Excretion: Mostly excreted unchanged in bile; 4.5% excreted unchanged in urine.
Half-life: 11–14 hr after single dose; 2–4 days after several doses.
TIME/ACTION PROFILE (serum)
ROUTE | ONSET | PEAK | DURATION |
---|---|---|---|
PO | rapid | 2.5–3.2 hr | 24 hr |
IV | rapid | end of infusion | 24 hr |
Contraindicated in:
Use Cautiously in:
CV: QT interval prolongation, CARDIOVASCULAR DEATH, chest pain, hypotension, palpitations, TORSADES DE POINTES
Derm: ACUTE GENERALIZED EXANTHEMATOUS PUSTULOSIS, DRUG REACTION WITH EOSINOPHILIA AND SYSTEMIC SYMPTOMS (DRESS), photosensitivity, rash, STEVENS-JOHNSON SYNDROME, TOXIC EPIDERMAL NECROLYSIS
EENT: ototoxicity
F and E: hyperkalemia
GI: abdominal pain, diarrhea, nausea, ↑ liver enzymes, cholestatic jaundice, CLOSTRIDIOIDES DIFFICILE-ASSOCIATED DIARRHEA (CDAD), dyspepsia, flatulence, HEPATOTOXICITY, melena, oral candidiasis, pyloric stenosis
GU: nephritis, vaginitis
Hemat: anemia, leukopenia, thrombocytopenia
Neuro: dizziness, drowsiness, fatigue, headache, seizures
Misc: HYPERSENSITIVITY REACTIONS (including anaphylaxis and angioedema)
* CAPITALS indicate life-threatening.
Underline indicate most frequent.
Drug-Drug
Quinidine, procainamide, dofetilide, sotalol, and amiodarone may ↑ risk of QT interval prolongation; concurrent use should be avoided.
Most Respiratory and Skin Infections
PO (Adults): 500 mg on 1st day, then 250 mg/day for 4 more days (total dose of 1.5 g); Acute bacterial sinusitis: 500 mg once daily for 3 days.
PO (Children ≥ 6 mo): Pneumonia/Pertussis: 10 mg/kg (not to exceed 500 mg/dose) on 1st day, then 5 mg/kg once daily (not to exceed 250 mg/dose) for 4 more days. Pharyngitis/tonsilitis: 12 mg/kg once daily for 5 days (not to exceed 500 mg/dose); Acute bacterial sinusitis: 10 mg/kg once daily for 3 days.
PO (Neonates): Pertussis, treatment and post-exposure prophylaxis: 10 mg/kg once daily for 5 days.
Otitis Media
PO (Children ≥6 mo): 30 mg/kg single dose (not to exceed 1500 mg/dose) or 10 mg/kg once daily (not to exceed 500 mg/dose) for 3 days or 10 mg/kg (not to exceed 500 mg/dose) on 1st day, then 5 mg/kg once daily (not to exceed 250 mg/dose) for 4 more days.
Acute Bacterial Exacerbations of Chronic Bronchitis
PO (Adults): 500 mg on 1st day, then 250 mg once daily for 4 more days (total dose of 1.5 g) or 500 mg once daily for 3 days.
Community-Acquired Pneumonia
IV PO (Adults): More severe: 500 mg IV every 24 hr for at least 2 doses, then 500 mg PO every 24 hr for a total of 7–10 days; Less severe: 500 mg PO, then 250 mg/day PO for 4 more days.
PO (Children >6 mo): 10 mg/kg on 1st day, then 5 mg/kg once daily for 4 more days.
Pelvic Inflammatory Disease
IV PO (Adults): 500 mg IV every 24 hr for 1–2 days, then 250 mg PO every 24 hr for a total of 7 days.
Endocarditis Prophylaxis
PO (Adults): 500 mg 1 hr before procedure.
PO (Children): 15 mg/kg 1 hr before procedure.
Nongonococcal Urethritis, Cervicitis, Chancroid, Chlamydia
PO (Adults): Single 1-g dose.
PO (Children): Chancroid: Single 20-mg/kg dose (not to exceed 1000 mg/dose). Urethritis or cervicitis: Single 10-mg/kg dose (not >1000 mg/dose).
Gonorrhea
PO (Adults): Single 2-g dose.
Prevention of Disseminated MAC Infection
PO (Adults): 1.2 g once weekly (alone or with rifabutin).
PO (Children): 5 mg/kg once daily (not >250 mg/dose) or 20 mg/kg (not >1200 mg/dose) once weekly (alone or with rifabutin).
Cystic Fibrosis
PO (Children ≥6 yrs, ≥40 kg): 500 mg every Monday, Wednesday, and Friday.
PO (Children ≥6 yrs, 25 kg to <40 kg): 250 mg every Monday, Wednesday, and Friday.
Tablets: 250 mg, 500 mg, 600 mg
Powder for oral suspension (cherry and banana flavor) : 1 g/pkt
Powder for oral suspension (cherry, creme de vanilla, and banana flavor) : 100 mg/5 mL, 200 mg/5 mL
Powder for injection : 500 mg/vial
Observe for signs and symptoms of anaphylaxis (rash, pruritus, laryngeal edema, wheezing). Notify health care professional immediately if these occur.
Assess patient for skin rash frequently during therapy. Discontinue azithromycin at first sign of rash; may be life-threatening. Stevens-Johnson syndrome or toxic epidermal necrolysis may develop. Treat symptomatically; may recur once treatment is stopped.
Lab Test Considerations:
May cause ↑ serum bilirubin, AST, ALT, LDH, and alkaline phosphatase concentrations.
Advise patient to report symptoms of chest pain, palpitations, yellowing of skin or eyes, or signs of superinfection (black, furry overgrowth on the tongue; vaginal itching or discharge; loose or foul-smelling stools) or rash.
Instruct patient to notify health care professional if fever and diarrhea develop, especially if stool contains blood, pus, or mucus. Advise patient not to treat diarrhea without advice of health care professional.
Resolution of the signs and symptoms of infection. Length of time for complete resolution depends on the organism and site of infection.