I AM ON WARFARIN AND HAVE BLOOD WORK DONE MONTHLY, ON THE 11/1 I HAD BLOOD WORK (PROTIME) TEST DONE AS USUAL. THE RESULTS WERE IT WAS TOO HIGH, MY DR. CHANGED DOSE FOR 4 DAYS AND I HAD TO DO BLOOD WORK AGAIN. DR. ADJUSTED WARFARIN AND ANOTHER BLOOD WORK 7 DAYS LATER, IT WAS STILL TO HIGH OFF WARFARIN 3 MORE DAYS AND BLOOD WORK AGAIN. WHAT COULD BE CAUSING MY PROTIME TO BE SO HIGH? KP