Yes, please contact your doctor immediately. Bleeding from your GI tract (stool), your nose, and in your urine (bleeding from your gums can have multiple causes and is not lifethreatening) are common causes of supratherapeutic warfarin dosing. If he has been controlled on warfarin before and this is a recent occurance you should check the following: Have you been consuming more or less green leafy vegetables than you usually do? Foods high in VItamin K can interfere with the efficacy of warfarin. Has he consumed alcohol acutely? 2 drinks Warfarin is composed of two epimers of the same drug, basically two versions of the same drug. One of the epimers is metabolized heavily by the liver and can be impeded by acute alcohol intake. Has he been taking any of the following? Aspirin, OTC pain medications (besides tylenol), Gingko Biloba, Garlic, higher doses of Vit C and Vit E (found in multivitamins) These medications can increase the risk of serious bleeds within the body. If you answered yes to any of the following it would be in your best interest to contact your doctor and tell him so. Warfarin has very personal dosing parameters and is maintainable with almost any lifestyle (save for binge drinking). Your next course of action is to return to your doctor, tell him that you are bleeding from your nose on a fairly regular basis and ask that he send out bloodwork for an INR. This is the study of the ability of the blood to clot and is used fairly exclusively for warfarin therapy. If he has been on the drug long I m sure you are already familiar with it. Good luck and I hope you are well.