Similar stories abound on this site but here is another story that demonstrates why we as heart valve patients taking warfarin should take pause before automatically following the instructions of our medical providers: Last Sunday I took my weekly home blood test which showed my INR to be 3.8, slightly above my range of 2.5-3.5. I reported this on-line as I do every week and proceeded to enjoy a little extra broccoli that night to remedy the situation. Since I am in range 90% of the time and since this reading was all but insignificant, I thought nothing about it again until today (5 days later) when I received a call from my doctor's office directing me to take 1/2 of my regular 7.5 milligram dose tonight to correct my high reading of 5 days ago. Well of course that was ridiculous but nevertheless I dutifully acknowledged their instructions before hanging up and proceeding to take my full regular dose. My PCP's instructions erroneously assumed that my elevated INR from last Sunday stayed the same until today and also assumed that I ignored the reading without taking any action and just sat around all week waiting to be told what to do about it. It also assumed that taking 3.75 milligrams of warfarin (which would be almost impossible to do) was the correct course of action in the first place. I actually considered taking 5 milligrams rather than 7.5 milligrams last Sunday, which would have made more sense, but decided instead that eating the broccoli would be much more enjoyable. Finally, since I am testing again in 2 days it makes more sense to wait until then to see if I need to make a dosage adjustment. Although most of us, at least in the U.S., are not permitted to self- manage our warfarin even when self-testing at home, in reality that is exactly what we should be doing. You know best how certain foods and various warfarin dosages affect your INR, and if you don't, you should.