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Moxifloxacin-warfarin interaction

Yan Ji1, Youssef Hokayem

  • 1Department of Medicine, Union Memorial Hospital, Baltimore, MD, USA.

Journal of Community Hospital Internal Medicine Perspectives
|July 25, 2013
PubMed

Insights

Warfarin and moxifloxacin coadministration can elevate prothrombin time/international normalized ratios (PT/INR). Healthcare providers should monitor INR closely in patients on warfarin, particularly those with low albumin, when prescribing moxifloxacin.

Area of Science:

  • Pharmacology
  • Drug Interactions
  • Clinical Medicine

Background:

  • Warfarin is a widely prescribed anticoagulant.
  • Moxifloxacin is a fluoroquinolone antibiotic.
  • Drug interactions can alter therapeutic efficacy and safety.

Observation:

  • Two case reports detail elevated prothrombin time/international normalized ratios (PT/INR).
  • These elevations occurred after coadministration of warfarin and moxifloxacin.
  • Low albumin levels were noted in affected patients.

Findings:

  • A potential interaction exists between warfarin and moxifloxacin.
  • The precise mechanism of this interaction is currently unknown.
  • Elevated PT/INR suggests increased anticoagulation effect.

Implications:

  • Healthcare providers must exercise caution when prescribing moxifloxacin to patients on warfarin.
  • Increased vigilance and frequent INR monitoring are recommended for patients with low albumin levels.
  • This interaction highlights the importance of comprehensive drug interaction surveillance.
Keywords:
PT/INRhypoalbuminemiamoxifloxacinwarfarin

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