title: Adverse interaction between capecitabine and warfarin resulting in altered coagulation parameters and bleeding: case report and review of the literature.
abstract: Capecitabine can interact with warfarin, resulting in altered coagulation parameters and bleeding. Four cases have been reported. We describe a fifth case with life-threatening interaction between these two drugs. A 67-year-old female with metastatic breast cancer developed hemorrhagic blisters, purpura and ecchymoses. She had been well controlled on long-term warfarin (5 mg/day). Capecitabine was initiated 4.5 weeks prior to the bleeding episode. Laboratory work-up revealed an international normalized ratio of 8.56, partial prothrombin time of 61 seconds and prothrombin time of 5.2%. The coagulation parameters gradually normalized within 4 days following vitamin K administration and discontinuation of capecitabine and warfarin. Careful monitoring of coagulation parameters and proper adjustment of the warfarin dose are required in patients taking warfarin and capecitabine concomitantly.
authors.affiliation: Department of Oncology, Rambam Medical Center and Faculty of Medicine, Technion-Israel Institute of Technology, Haifa, Israel.
authors.forename: K
authors.initials: K
authors.lastname: Isaacs
authors.forename: N
authors.initials: N
authors.lastname: Haim
mesh_terms: D000368:Aged; D000925:Anticoagulants / Q000008:administration & dosage / Q000009:adverse effects* / Q000627:therapeutic use*; D000964:Antimetabolites, Antineoplastic / Q000009:adverse effects* / Q000627:therapeutic use*; D001943:Breast Neoplasms / Q000188:drug therapy; D000069287:Capecitabine; D003841:Deoxycytidine / Q000009:adverse effects / Q000031:analogs & derivatives* / Q000627:therapeutic use; D004347:Drug Interactions; D005260:Female; D005472:Fluorouracil / Q000031:analogs & derivatives; D006470:Hemorrhage / Q000139:chemically induced; D006801:Humans; D014859:Warfarin / Q000008:administration & dosage / Q000009:adverse effects* / Q000627:therapeutic use*
chemical_list: D000925:Anticoagulants; D000964:Antimetabolites, Antineoplastic; D003841:Deoxycytidine; D014859:Warfarin; D000069287:Capecitabine; D005472:Fluorouracil