Bioavailability of warfarin in a patient with severe short bowel syndrome.
Acquired warfarin resistance has resulted from altered drug metabolism and excessive vitamin K. A third possible mechanism, decreased gastrointestinal absorption of the drug, was examined in a patient with short bowel syndrome and severe malabsorption who demonstrated transient warfarin resistance. Despite the resistance, bioavailability studies demonstrated normal drug absorption and a prolonged half-life. The parenteral administration of vitamin K proved to be the cause of the prolonged warfarin resistance.
D000328:Adult; D001682:Biological Availability; D004351:Drug Resistance; D005260:Female; D006207:Half-Life; D006801:Humans; D007279:Injections, Subcutaneous; D007408:Intestinal Absorption; D008286:Malabsorption Syndromes / Q000378:metabolism*; D012778:Short Bowel Syndrome / Q000378:metabolism*; D014812:Vitamin K / Q000008:administration & dosage; D014859:Warfarin / Q000378:metabolism*
D014812:Vitamin K; D014859:Warfarin