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Panwarfin

Interactions

Selected Anticoagulants/Selected Macrolide Antibiotics

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 the blood thinner more slowly.

What might happen:

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:

Contact your doctor as soon as possible if you are taking these two medicines.You should watch for any unusual bleeding or bruising. Your bleeding times may need to be monitored and the dose of your blood thinner adjusted, or you may need to be switched to a different antibiotic.You should maintain good nutrition while on these medicines. This drug interaction may be more likely to occur if you are elderly or if you are taking larger doses of the antibiotic.Make sure that your doctor knows all of the medicines that you are taking. Your healthcare professionals (e.g. doctor or pharmacist) may already be aware of this interaction and may be monitoring you for it. Do not stop, start, or change the dosage of any medicine before checking with them first.

References:

1.Beckey NP, Parra D, Colon A. Retrospective evaluation of a potential interaction between azithromycine and warfarin in patients stabilized on warfarin. Pharmacotherapy 2000 Sep;20(9):1055-9.

2.McCall KL, Anderson HG Jr, Jones AD. Determination of the lack of a drug interaction between azithromycin and warfarin. Pharmacotherapy 2004 Feb; 24(2):188-94.

3.Rao KB, Pallaki M, Tolbert SR, Hornick TR. Enhanced hypoprothrombinemia with warfarin due to azithromycin. Ann Pharmacother 2004 Jun;38(6):982-5.

4.Foster DR, Milan NL. Potential interaction between azithromycin and warfarin. Pharmacotherapy 1999 Jul;19(7):902-8.

5.Shrader SP, Fermo JD, Dzikowski AL. Azithromycin and warfarin interaction. Pharmacotherapy 2004 Jul;24(7):945-9.

6.Woldtvedt BR, Cahoon CL, Bradley LA, Miller SJ. Possible increased anticoagulation effect of warfarin induced by azithromycin. Ann Pharmacother 1998 Feb;32(2):269-70.

7.Lane G. Increased hypoprothrombinemic effect of warfarin possibly induced by azithromycin. Ann Pharmacother 1996 Jul-Aug;30(7-8):884-5.

8.Grau E, Real E, Pastor E. Interaction between clarithromycin and oral anticoagulants. Ann Pharmacother 1996 Dec;30(12):1495-6.

9.Recker MW, Kier KL. Potential interaction between clarithromycin and warfarin. Ann Pharmacother 1997 Sep;31(9):996-8.

10.Oberg KC. Delayed elevation of international normalized ratio with concurrent clarithromycin and warfarin therapy. Pharmacotherapy 1998 Mar-Apr;18(2):386-91.

11.Gooderham MJ, Bolli P, Fernandez PG. Concomitant digoxin toxicity and warfarin interaction in a patient receiving clarithromycin. Ann Pharmacother 1999 Jul-Aug;33(7-8):796-9.

12.Weibert RT, Lorentz SM, Townsend RJ, Cook CE, Klauber MR, Jagger PI. Effect of erythromycin in patients receiving long-term warfarin therapy. Clin Pharm 1989 Mar;8(3):210-4.

13.Bachmann K, Schwartz JI, Forney R Jr, Frogameni A, Jauregui LE. The effect of erythromycin on the disposition kinetics of warfarin. Pharmacology 1984;28(3):171-6.

14.Bussey HI, Knodel LC, Boyle DA. Warfarin-erythromycin interaction. Arch Intern Med 1985 Sep;145(9):1736-7.

15.Schwartz J, Bachmann K, Perrigo E. Interaction between warfarin and erythromycin. South Med J 1983 Jan;76(1):91-3.

16.Hassell D, Utt JK. Suspected interaction: warfarin and erythromycin. South Med J 1985 Aug;78(8):1015-6.

17.Sato RI, Gray DR, Brown SE. Warfarin interaction with erythromycin. Arch Intern Med 1984 Dec;144(12):2413-4.

18.Husserl FE. Erythromycin-warfarin interaction. Arch Intern Med 1983 Sep; 143(9):1831, 1836.

19.Bartle WR. Possible warfarin-erythromycin interaction. Arch Intern Med 1980 Jul;140(7):985-7.

20.Grau E, Fontcuberta J, Felez J. Erythromycin-oral anticoagulants interaction. Arch Intern Med 1986 Aug;146(8):1639.

21.Paulsen O, Nilsson LG, Saint-Salvi B, Manuel C, Lunell E. No effect of roxithromycin on pharmacokinetic or pharmacodynamic properties of warfarin and its enantiomers. Pharmacol Toxicol 1988 Oct;63(4):215-20.

22.Chassany O, Logeart I, Choulika S, Caulin C. Parietal abdominal hematoma after combined acenocoumarol and roxithromycin treatment. Presse Med 1998 Jun 20;27(22):1103.

23.Kolilekas L, Anagnostopoulos GK, Lampaditis I, Eleftheriadis I. Potential interaction between telithromycin and warfarin. Ann Pharmacother 2004 Sep;38(9):1424-7.

24.Djelouah I. Telithromycin (ketek) and warfarin: suspected interaction. Canadian Adverse Reaction Newsletter 2005 Jan;15(1):1-2.

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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