The safety of anticoagulant administration has been a primary concern of medical research. Among all anticoagulants, warfarin has long been listed among the top ten drugs causing adverse drug events. This oral anticoagulant is widely used as an effective preventative treatment for thromboembolic problems such as strokes and heart attacks. However, it requires individualized dosing that accounts for numerous factors, since slight overdosing or underdosing can have catastrophic or even fatal consequences. Warfarin titration via International Normalized Ratio (INR) monitoring can be challenging due to its narrow therapeutic window and complex individual factor relationships, multiple drugs and food interactions, its long half-life, and the patient's individual response to a given dose, significant side effects. You can predict the reasonable range of Warfarin dosage in your case, by answering a few questions about your drug, desease, and habit backgrounds: