Many people, but not all, with Lupus also have a condition called Antiphospholipid (APS) or Hughes syndrome in which the blood clots more easily and can therefore cause vascular thromboses. One of the main treatments is to take daily Warfarin (Coumadin) tablets.

How Warfarin works

First, you should know that your liver uses vitamin K to make blood clotting proteins. In doing so, vitamin K plays a role in your body’s natural clotting process. Vitamin K is contained largely in leafy green vegetables but also in other foods in varying amounts. Warfarin destroys Vitamin K, thus reducing the rate at which the blood clots ie the coagulation rate. So, eating a lot of foods containing Vitamin K, clotting time is increased. The aim of anticoagulation is to slow down clotting time but not to cut out those healthy foods. It is really a balancing act to get the right dose of Warfarin.

Monitoring the coagulation rate

Scientists have come up with an internationally accepted way of measuring the rate at which the blood clots. This is called the INR (the international normalised ratio) and for people with lupus this measurement is usually set at around 3 although some consultants will argue that it should be higher, 3-4. This will be monitored at a community or hospital anticoagulation clinic where a sample of blood can be taken from a finger prick (capillary blood) or from a vein (venous blood).

It is, however, becoming more common for people to have their own machine and carry out self monitoring thus visiting the clinic less frequently. This means that one can go away for longer periods, keep a check on the INR and have peace of mind.

False high INR values

It is useful to note that Antiphospholipid antibodies and Lupus antibodies may cause false-high INR values and so clinics may wish to compare the capillary samples with a venous samples, which will be more accurate.

Getting used to being on Warfarin

It can be quite alarming initially to be told that you have to take Warfarin but like all the other hassles we have to go through with Lupus, in time, one gets used to it and accepts that it is preventing possible problems in the future.

Judith Orford
6.11.2015