Azithromycin

C. diff Risk

Medium

Oral Bioavailability

Moderate

Approximate Cost

Dosing

Adult

Respiratory Infection:
500mg PO/IV on day 1 then 250mg daily for 4 days

Sinusitis: 500 mg po daily x 3 days

Chlamydia, Chanchroid: refer to Canadian Guidelines to Sexually Transmitted Infections for full management: typically 1000 mg po as a single dose

Consult specialist, Pharmacy or specific treatment guidelines for additional dosing regimens, including prophylaxis.

Renal

No adjustment required

General Information

Common Usage

  • Community acquired pneumonia

  • Pertussis

  • Upper respiratory tract infections

  • Chlamidial infections

  • Mycobacterial infections

  • Mycobacterium avium complex (MAC) prophylaxis in HIV patients

Drug Monitoring

Monitor QTc in patients with increased risk

Adverse Effects

Prolongation of QTc interval. Association with increased cardiovascular mortality in observational studies.

Prolonged half life may contribute to macrolide resistance

Major Interactions

  • Other drugs that prolong QTc

  • Increases cyclosporine levels

  • May increase digoxin levels

  • Statins increased risk of rhabdomyolysis

Additional Information

Very high tissue penetration and concentration intracellularly means in vivo activity may not be predicted by in vitro testing - e.g. Salmonella species.

Pharmacology

Antimicrobial class: Macrolide

Pregnancy category: B

Average serum half life: 68 hours

Biliary penetration: Therapeutic

CSF penetration: Poor

Lung penetration: Therapeutic

Urine penetration: Poor