Antimicrobials
Clarithromycin

Clarithromycin

Medium
Moderate (40 to 70%)

Spectrum of Activity

Dosing

General Information

  • BUN, creatinine

  • LFTs

  • Audiogram with prolonged use

  • ECG for QTc prolongation

Refer to drug interaction checker for comprehensive list; major substrate & inhibitor of CYP3A

  • Absorption
    • Rapid
    • Food delays rate, but not extent of absorption
  • Distribution: Widely into most body tissues
  • Protein Binding: 42% to 70%
  • Metabolism
    • Partially hepatic via CYP3A4
    • Converted to 14-OH clarithromycin (active metabolite)
    • Undergoes extensive first-pass metabolism
  • Bioavailability: ~50%
  • Half-Life Elimination
    • Clarithromycin: 3-7 hours
    • 14-OH-clarithromycin: 5-9 hours
  • Time to Peak: 2-3 hrs
  • Excretion
    • Urine (20% to 40% as unchanged drug; additional 10% to 15% as metabolite)
    • Feces (29% to 40% mostly as metabolites)