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Drug Class: Commonly Known As: Category:
Anticoagulant Marevan® Adult

Warfarin - Dosage and How to Use

How should Warfarin be used?

  • Warfarin can be taken with or without food
  • Take at the same time, once daily
  • DO NOT miss, double or adjust your dose unless directed by your doctor or pharmacist

What happens when you start Warfarin

  • You will be given a booklet called Anticoagulation Therapy Record that provides an ongoing record of your blood tests and warfarin dosage
  • Remember to bring the booklet with you every time you visit Anticogulation Clinic
  • Warfarin dose is adjusted according to your desired International Normalised Ration (INR) that measures the effectiveness of warfarin and its bleeding risk
  • Your desired INR range is: _____________________
  • Blood tests may be required more frequently to determine the appropriate warfarin dose
  • Your dose may change after each visit depending on your INR result. Your doctor or pharmacist will inform you any dose changes
  • Inform your doctor or pharmacist of any illnesses, hospitalisation, changes in medication(s) or lifestyle at your next appointment
  • Inform other healthcare professionals (doctors, dentist, pharmacist) whom you are seeing for other condition(s) that you are on warfarin

What should I do if I miss a dose?

  • Take it as soon as you remember if it is within 8 hours of your usual time to take warfarin
  • If it is after 8 hours, skip the dose for that day
  • Just take your warfarin dose at the usual time the next day
  • DO NOT take double doses, unless your doctor tells you to, as this can cause excessive bleeding
  • Record the dates on which you missed your dose(s). Inform your doctor at your next appointment

What should I do if I overdose?

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