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Fenofibrate and warfarin interaction

M A Aldridge1, M K Ito

  • 1University of Pacific, Stockton, California, and Veterans Administration San Diego Healthcare System, USA.

Pharmacotherapy
|July 11, 2001
PubMed

Insights

Fenofibrate therapy initiation in patients on warfarin may increase bleeding risk. Close international normalized ratio (INR) monitoring is crucial to prevent supratherapeutic INR values and potential hemorrhagic events.

Area of Science:

  • Pharmacology
  • Clinical Medicine

Background:

  • Warfarin (Coumadin) is a common anticoagulant for atrial fibrillation and coronary heart disease.
  • Fenofibrate is used to manage elevated triglyceride levels.

Observation:

  • A 79-year-old male patient on warfarin experienced rectal bleeding after switching from gemfibrozil to fenofibrate.
  • His international normalized ratio (INR) became significantly elevated post-fenofibrate initiation.

Findings:

  • Fenofibrate therapy was associated with a supratherapeutic INR in a patient stabilized on warfarin.
  • No other changes in medication, diet, or lifestyle were reported by the patient.

Implications:

  • Clinicians must perform serial INR monitoring when initiating fenofibrate in patients on warfarin.
  • This monitoring is essential to mitigate the risk of bleeding events.
  • Careful drug interaction surveillance is vital for patient safety.

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