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    Selected Anticoagulants (Vit K antagonists)/Chloramphenicol

    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, chloramphenicol may decrease the ability of your blood to clot properly.

    What might happen:

    You may experience an increased chance for bleeding.

    What you should do about this interaction:

    You may need to have your bleeding time checked more often. If you experience unusual bruising, bleeding from the gums, nosebleeds, or blood in your urine or stool, contact your healthcare professional (e.g. doctor or pharmacist) right away.Your healthcare professionals may already be aware of this drug interaction and may be monitoring you for it. Do not start, stop, or change the dosage of any medicine before checking with your doctor first.


    1.Magid E. Tolerance to anticoagulants during antibiotic therapy. Scand J Clin Lab Invest 1962;14:565-6.

    2.Udall JA. Human sources and absorption of vitamin K in relation to anticoagulation stability. JAMA 1965 Oct 11;194(2):127-9.

    3.Frick PG, Riedler G, Brogli H. Dose response and minimal daily requirement for vitamin K in man. J Appl Physiol 1967 Sep;23(3):387-9.

    4.Christensen LK, Skovsted L. Inhibition of drug metabolism by chloramphenicol. Lancet 1969 Dec 27;2(7635):1397-9.

    5.Matsaniotis N, Messaritakis J, Vlachou C. Hypoprothrombinaemic bleeding in infants associated with diarrhea and antibiotics. Report of two cases. Arch Dis Child 1970 Aug;45(242):586-7.

    6.Yacobi A, Lai CM, Levy G. Pharmacokinetic and pharmacodynamic studies of acute interaction between warfarin enantiomers and chloramphenicol in rats. J Pharmacol Exp Ther 1984 Oct;231(1):80-4.

    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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