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azithromycin
Zithromax

Pregnancy Risk Category B

How supplied
Capsules:
250 mg; Z-pak (contains 5 days of therapy)
Injection:
500 mg
Oral suspension:
100 mg/5 ml, 200 mg/5 ml
Single-dose powder for oral suspension:
1 g
Tablets:
250 mg, 600 mg

Action
Binds to the 50S subunit of bacterial ribosomes, blocking protein synthesis; bacteriostatic or bactericidal, depending on concentration.

Indications & dosage
Acute bacterial exacerbations of COPD due to
Haemophilus influenzae, Moraxella (Branhamella) catarrhalis, or Streptococcus pneumoniae; uncomplicated skin and skin-structure infections due to Staphylococcus aureus, Streptococcus pyogenes, or S. agalactiae; second-line therapy of pharyngitis or tonsillitis due to S. pyogenes--
Adults and adolescents ages 16 and older:
500 mg P.O. as a single dose on day 1; then 250 mg daily on days 2 through 5. Total dose is 1.5 g.
Community-acquired pneumonia due to
Chlamydia pneumoniae, H. influenzae, Mycoplasma pneumoniae, S. pneumoniae; I.V. form can also be used for Legionella pneumophila, M. catarrhalis, and S. aureus--
Adults and adolescents ages 16 and older:
500 mg P.O. as a single dose on day 1; then 250 mg P.O. daily on days 2 through 5. Total dose is 1.5 g. For patients requiring initial I.V. therapy, 500 mg I.V. as a single daily dose for 2 days; then 500 mg P.O. as a single daily dose to complete a 7-to 10-day course of therapy. Switch from I.V. to P.O. therapy should be done at the doctor's discretion and based on patient's clinical response.
Nongonococcal urethritis or cervicitis due to
C. trachomatis--
Adults and adolescents ages 16 and older:
1 g P.O. as a single dose.
Prevention of disseminated
Mycobacterium avium complex disease in patients with advanced HIV infection--
Adults:
1,200 mg P.O. once weekly, as indicated.
Urethritis and cervicitis due to
Neisseria gonorrhoeae--
Adults:
2 g P.O. as a single dose.
Pelvic inflammatory disease due to
C. trachomatis, N. gonorrhoeae, or M. hominis in patients who require initial I.V. therapy--
Adults:
500 mg I.V. as a single daily dose for 1 to 2 days; then 250 mg P.O. daily to complete a 7-day course of therapy. Switch from I.V. to P.O. therapy should be at doctor's discretion and based on patient's clinical response.
Genital ulcer disease in men caused by
H. ducreyi (chancroid)--
Adults:
1 g P.O. as a single dose.
Otitis media--

Children over age 6 months:
10 mg/kg (maximum 500 mg) P.O. on day 1; then 5 mg/kg (maximum 250 mg) on days 2
to 5.
Pharyngitis, tonsillitis--

Children over age 2:
12 mg/kg (maximum 500 mg) P.O. daily for 5 days.
Dental prophylaxis in patients allergic to penicillin--

Adults:
500 mg P.O. 1 hour before procedure.
Children:
15 mg/kg P.O. 1 hour before procedure.

Adverse reactions
CNS:
dizziness, vertigo, headache, fatigue, somnolence.
CV:
palpitations, chest pain.
GI:
nausea, vomiting, diarrhea, abdominal pain, dyspepsia, flatulence, melena, cholestatic jaundice, pseudomembranous colitis.
GU:
candidiasis, vaginitis, nephritis.
Skin:
rash, photosensitivity.
Other:
angioedema.

Interactions
Drug-drug.
Aluminum- and magnesium-containing antacids: lowered peak plasma levels of azithromycin. Separate administration times by at least 2 hours.
Carbamazepine, cyclosporine, phenytoin:
may increase levels of these drugs. Monitor closely.
Digoxin:
may cause elevated digoxin levels. Monitor closely.
Ergotamine:
acute ergotamine toxicity has occurred. Monitor closely.
Pimozide:
prolongation of QT interval and ventricular tachycardia have been associated with other macrolide anti-infectives. Monitor patient closely.
Theophylline:
may increase plasma theophylline levels with other macrolides; effect of azithromycin is unknown. Monitor theophylline levels carefully.
Triazolam:
may decrease clearance of triazolam. Monitor closely.
Warfarin:
may increase INR with other macrolides; effect of azithromycin is unknown. Monitor INR carefully.
Drug-food.
Any food: decreased absorption of capsules and multidose oral suspension formulation. Take the preparations on an empty stomach.
Drug-lifestyle.
Sun exposure: photosensitivity reactions may occur. Take precautions.

Effects on diagnostic tests
None reported.

Contraindications
Contraindicated in patients with hypersensitivity to erythromycin or other macrolides.

Nursing considerations

I.V. administration

Patient teaching

*Liquid contains alcohol. **May contain tartrazine.  †Canada  ‡Australia  §U.K.  OTCOver the counter
Reactions may be common, uncommon, life-threatening, or COMMON AND LIFE-THREATENING

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