Warfarin is an anticoagulant. This is a medicine that stops blood from clotting.
It can be given to people if they are at risk of developing a blood clot (thrombosis) or if they have developed a clot and need treatment.
Warfarin is used to treat and prevent the following health conditions:
How long you will take warfarin depends on the condition for which it has been prescribed. If you are not sure, ask your GP.
You will also be given a yellow booklet on anticoagulants, which explains your treatment.
How it works
The blood needs vitamin K to be able to clot. Warfarin slows the production of vitamin K in the body, which increases the time it takes for your blood to clot. This is sometimes described as 'thinning the blood'.
Warfarin helps your blood to flow freely around your body and stops any clots forming in the heart or in the blood vessels.
Names
Warfarin is the main oral anticoagulant used in the UK (oral means that it is taken by mouth).
Occasionally, people may be given other anticoagulant tablets. These are called acenocoumarol (brand name Sinthrome) and phenindione. These are not commonly used in the UK but are used in other countries.
