Antimicrobials
Azithromycin

Azithromycin

C difficile risk
Medium
Oral Bioavailability
See Additional Information
Cost
PO: 1.63$ IV: 12.93$

Dosing

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

1g as single dose with 250mg ceftriaxone IM

General Information

  • Community acquired pneumonia

  • Pertussis

  • Upper respiratory tract infections

  • Chlamydial infections

  • Mycobacterial infections

  • Mycobacterium avium complex (MAC) prophylaxis in HIV patients

Monitor QTc in patients with increased risk

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

Prolonged half life may contribute to macrolide resistance.

  • Other drugs that prolong QTc

  • Increases cyclosporine levels

  • May increase digoxin levels

  • Statins increased risk of rhabdomyolysis

Bioavailability: 37% - low

  • The low bioavailability is compensated with very high tissue penetration.

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

Antimicrobial class: Macrolide

Pregnancy category: B

Average serum half life: 68 hours

Urine penetration: Poor

Lung penetration: Therapeutic

CSF penetration: Poor

Biliary penetration: Therapeutic