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People living with RHD need to be on medication to reduce the risk of blood clots which can cause stroke. This medication makes the blood ‘thinner’ and less likely to clot. Medication may be needed if you have a heart valve replacement operation or an abnormal heart rhythm (atrial fibrillation).

The most common anticoagulation medicine is called warfarin. Different people need different amounts of warfarin to keep their blood thin. Regular blood tests called INR (international normalised ratio) are needed to check whether the right dose of warfarin is given. Your doctor or nurse may change the dose of warfarin after each blood test.

It is important to remember:

  • Warfarin makes you blood slower to clot (stop bleeding). This means that wounds or injuries can be more dangerous. Many people on warfarin carry a card or wear a bracelet to let other people know they are on warfarin if they are injured or unable to communicate.
  • Always tell doctors, nurses or health professionals that you take warfarin. Warfarin may change the other kinds of medicines and treatment which are best for you
  • Women who take warfarin should talk to a health professional before becoming pregnant or as soon they find out they are pregnant. Warfarin is a strong medicine which can dangerous for mothers and babies. Stopping warfarin can also be very dangerous. Do not stop taking your warfarin tablets without talking to a doctor.

There are lots of things you can do to help keep your INR level stable and minimise complications from taking warfarin. These include

  • Taking your warfarin at the same time each day.
  • Maintain a regular diet. Some food and drink (including green leafy vegetables and alcohol) can change the way your body uses warfarin, making your INR go up or down.

More information about taking warfarin has been compiled by the American Heart Association and UpToDate.

Point of care anticoagulation device