|To evaluate a patient who appears to be warfarin resistant.|
|Cardiovascular Diseases, Vascular Medicine, Clinical Pharmacology, Pharmaceutical Medicine|
|clinical diagnosis, including family history for genetics, laboratory tests, failure handling and therapy escalation, response to therapy, drug levels, overdose and reversal|
|I74, I81, I82, O88|
Warfarin resistance refers to the need for high doses of warfarin (20 mg or more per day) to achieve a therapeutic increase in the prothrombin time (PT) and INR.