Women who take the prescription blood-thinner warfarin should consult their doctor or pharmacist for advice before using an OTC vaginal miconazole product, according to the U.S. Food and Drug Administration (FDA).
Vaginal creams and suppositories containing miconazole must include the following warning in the "Drugs Facts" box on product labels: Ask a doctor or pharmacist before use if you are taking the prescription blood thinning medicine warfarin, because bleeding or bruising may occur.
The FDA took this action because the agency received two adverse events indicating abnormal blood clotting tests with women who took anticoagulant therapy and used vaginal miconazole. In addition to abnormal tests, one woman developed bruises, bleeding gums, and a nosebleed. Two articles from medical journals reported cases of probable warfarin interaction with vaginal miconazole. The agency believes that consumers should have all the information about a drug's potential risks before deciding to use it.
What Is Miconazole?
Miconazole is an antifungal drug that has been available by prescription and over-the-counter in different forms (such as creams and suppositories) for many years. The vaginal creams and suppositories are used to treat vaginal yeast infections.
The interaction of oral miconazole with warfarin is well established, and is included in the warfarin labeling. Because of the concerns raised by the reports of an interaction with vaginally administered miconazole with warfarin, patients who need to use both products at the same time should be appropriately monitored by their doctor. The cautionary label is included in consumer brochures in addition to being placed on the product labels. Products containing miconazole include the Monistat combination pack. |
