C. diff Risk


Oral Bioavailability


Approximate Cost

Spectrum Of Activity


250-500mg PO BID

CrCl Less Than 30 mL/min50% of dose BID

CrCl Greater Than 30 mL/min250-500 mg BID

General Information

Common Usage

  • CAP

  • Pertussis

  • URTI

  • H. pylorI and mycobacterial infections

Drug Monitoring

Monitor QTc in patients with increased risk

Adverse Effects

  • Neutropenia

  • GI upset

  • Prolongation of QTc interval

  • Drug interactions

Major Interactions

Recommend review of patient medications due to high frequency of significant interactions

  • ¬†CYP450 interactions ++

  • Other QTc prolonging agents

  • Statins - increased rhabdo

  • CCBs - hypotension, AKI

  • Colchicine - increased bone marrow toxicity

  • Increased anticonvulsant levels

  • Increased tacrolimus levels

Additional Information

Very high tissue penetration and concentration intracellularly means in vivo activity may not be predicted by in vitro testing


Antimicrobial class: Macrolide

Pregnancy category: C

Average serum half life: 5 hours

Biliary penetration: Therapeutic

CSF penetration: Poor

Lung penetration: Therapeutic

Urine penetration: Poor