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Warfarin is an anticoagulant (a drug which reduces the ability of your blood to clot) which is known to help people with some types of PAH. Warfarin tablets come in different doses and colours

Regular testing

People taking warfarin need to have their blood checked every 4–8 weeks to ensure the level of warfarin in the blood is at a beneficial amount. These blood test will be more frequently when you first start taking warfarin until the beneficial level is achieved. The doctor will want your blood to take twice as long to clot than normal.

This is measured using a blood test called INR. INR should measure between 2 and 3 on people taking warfarin. If your INR level is uncontrolled (too high or too low) the doctor or nurse may adjust your dose and take your bloods more frequently until the level settles.

Precautions when taking warfarin

While Warfarin is safe to take, it reduces the ability of your blood to clot. You are more likely to bruise or bleed for longer if you injure yourself, even minor bumps or scrapes.

If you experience any of the following while taking warfarin you should discuss with your doctor or nurse:

  • Prolonged bleeding from cuts.
  • Bleeding that does not stop by itself.
  • Nose bleeds.
  • Bleeding gums.
  • Red or dark brown coloured urine.
  • For women, increased bleeding during periods (or  any other vaginal bleeding).
  • If you suffer a head injury you should seek medical attention even if you feel fine.

Other medicines and remedies

Sometimes Warfarin can be affected by other medicines you may be taking, including medicines you can buy without a prescription and herbal remedies. Always check with your doctor before taking any new medicines or remedies. You should also tell your dentist, pharmacist and chiropodist.

Exercise and activity

There are no restrictions on activity or exercise while taking warfarin. However contact sports i.e. boxing, rugby are best avoided. If undertaking other sports i.e. skiing, cycling, protective equipment should always be worn.