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    Selected Anticoagulants/Capecitabine; Fluorouracil

    This information is generalized and not intended as specific medical advice. Consult your healthcare professional before taking or discontinuing any drug or commencing any course of treatment.

    Medical warning:

    Serious. These medicines may interact and cause very harmful effects. Contact your healthcare professional (e.g. doctor or pharmacist) for more information.

    How the interaction occurs:

    When these two medicines are taken together, your body may process your blood-thinner more slowly.

    What might happen:

    The effect of the blood-thinner may increase.You may experience an increased chance for bleeding including bleeding from your gums, nosebleeds, unusual bruising, or dark stools.

    What you should do about this interaction:

    Ask your healthcare professionals (e.g. doctor or pharmacist) about taking these medicines together. You may need to have your bleeding times (e.g. prothrombin, INR) checked more often while taking these medicines together and for at least a month after stopping capecitabine therapy. If you have any signs of bleeding, such as bleeding from your gums, nosebleeds, unusual bruising, or dark stools, contact your doctor right away.Your healthcare professionals may already be aware of this interaction and may be monitoring you for it. Do not start, stop, or change the dosage of any medicine before checking with them first.


    1.Xeloda (capecitabine) US prescribing information. Roche Pharmaceuticals March, 2015.

    2.Wajima T, Mukhopadhyay P. Possible interactions between warfarin and 5-fluorouracil. Am J Hematol 1992 Jul;40(3):238.

    3.Scarfe MA, Israel MK. Possible drug interaction between warfarin and combination of levamisole and fluorouracil. Ann Pharmacother 1994 Apr; 28(4):464-7.

    4.Brown MC. Multisite mucous membrane bleeding due to a possible interaction between warfarin and 5-fluorouracil. Pharmacotherapy 1997 May-Jun; 17(3):631-3.

    5.Brown MC. Interaction between warfarin and 5-fluorouracil, not between warfarin and levamisole. Clin Pharmacol Ther 1998 Aug;64(2):233.

    6.Brown MC. An adverse interaction between warfarin and 5-fluorouracil: A case report and review of the literature. Chemotherapy 1999 Sep-Oct; 45(5):392-5.

    7.Kolesar JM, Johnson CL, Freeberg BL, Berlin JD, Schiller JH. Warfarin-5-FU interaction--a consecutive case series. Pharmacotherapy 1999 Dec; 19(12):1445-9.

    8.Aki Z, Kotiloglu G, Ozyilkan O. A patient with a prolonged prothrombin time due to an adverse interaction between 5-fluorouracil and warfarin. Am J Gastroenterol 2000 Apr;95(4):1093-4.

    Selected from data included with permission and copyrighted by First Databank, Inc. This copyrighted material has been downloaded from a licensed data provider and is not for distribution, expect as may be authorized by the applicable terms of use.

    CONDITIONS OF USE: The information in this database is intended to supplement, not substitute for, the expertise and judgment of healthcare professionals. The information is not intended to cover all possible uses, directions, precautions, drug interactions or adverse effects, nor should it be construed to indicate that use of a particular drug is safe, appropriate or effective for you or anyone else. A healthcare professional should be consulted before taking any drug, changing any diet or commencing or discontinuing any course of treatment.

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