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Warfarin is a high-risk medicine. You can reduce harm from warfarin and measure its effectiveness with INR monitoring.

Check other medicines prescribed or purchased including alternative products.

  • Document the target INR.
  • Interactions can affect the INR and result in harm, for example:
    • many antibiotics and antifungals
    • some over-the-counter and alternative medicines
    • alcohol
    • green leafy vegetables.
  • Check the patient’s understanding of INR monitoring.

For more information, see these online resources.