Azole Antifungal Agents/Selected Anticoagulants
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 not process your blood-thinner properly.
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:
Your healthcare professionals (e.g. doctor or pharmacist) may already be aware of this interaction and may be monitoring you for it. If your doctor prescribes these two drugs together, you may need to have your bleeding times checked more often. If you have any signs of bleeding, such as bleeding from your gums, nosebleeds, unusual bruising, or dark stools, contact your doctor right away. You may need an adjustment in the dose of your blood thinner. Do not start, stop, or change the dosage of any medicine before checking with them first.
References:
1.Smith AG. Potentiation of oral anticoagulants by ketoconazole. Br Med J (Clin Res Ed) 1984 Jan 21;288(6412):188-9.
2.Colquhoun MC, Daly M, Stewart P, Beeley L. Interaction between warfarin and miconazole oral gel. Lancet 1987 Mar 21;1(8534):695-6.
3.Lazar JD, Wilner KD. Drug interactions with fluconazole. Rev Infect Dis 1990 Mar-Apr;12 Suppl 3:S327-33.
4.Seaton TL, Celum CL, Black DJ. Possible potentiation of warfarin by fluconazole. DICP 1990 Dec;24(12):1177-8.
5.Shenfield GM, Page M. Potentiation of warfarin action by miconazole oral gel. Aust N Z J Med 1991 Dec;21(6):928.
6.O'Reilly RA, Goulart DA, Kunze KL, Neal J, Gibaldi M, Eddy AC, Trager WF. Mechanisms of the stereoselective interaction between miconazole and racemic warfarin in human subjects. Clin Pharmacol Ther 1992 Jun; 51(6):656-67.
7.Vfend (voriconazole) US prescribing information. Pfizer Inc. November, 2011.
