Case Presentation of a 45 Years Old Woman with Hypoglycemia and Bleeding

Apatient was admitted to the hospital because of epistaxis, ecchymoses and gumbleeding with inr of 5.5. this patient had a known case of diabetes mellitus typeii, 5 years ago. the last dose of glibenclamide for managing signs and symptomsof diabetes mellitus was 20 mg/day. her medical history also showed that lastmonth she was diagnosed with atrial fibrillation with normal left ventricular ejectionfraction (lvef> 45%) and was placed on warfarin (5 mg) and propranolol (80 mg)daily, which resulted in resolution of atrial fibrilation, a pulse rate of 80 bps and inrof 3 (target inr=2-3). an objective causality assessment indicated the increased effectof warfarin and as a result bleeding could best be explained by drug-drug interactionbecause there are no other factors such as pathological evidences (e.g. thyroiddisease, hepatic disorders) to prove it otherwise. this case is the third report of druginteraction between warfarin and glibenclamide, therefore, this is an interesting andeducational case.in view of our experience in the present case, it should be stressed that closemonitoring of coagulation capacity is necessary in co-administration of warfarin andother drugs which can affect pharmacokinetic and pharmacodynamic of warfarin.