Patients being treated with warfarin are calling for blood test strips for the measurement of international normalised ratio (INR) to be made available on National Health Service prescription, in the same way as testing strips for monitoring blood glucose levels for diabetics. The INR is a measure of blood clotting time.
Letters making the plea, written by patients, were delivered to 10 Downing Street on February 23 by two teenagers who need regularly to monitor their clotting times because they have been fitted with artificial heart valves.