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Updated: Aug 29, 2026

Colletotrichum fioriniae Development in Water and Chloroform-based Blueberry and Cranberry Floral Extracts
Published on: April 12, 2019
Warfarin and cranberry juice: an interaction?
1Department of Surgery, William Harvey Hospital, Ashford, United Kingdom. drpaul.grant@orange.net
Abstract:
Herein, the case is reported of a persistently elevated INR consequent to an interaction between warfarin and cranberry juice in a patient with a prosthetic mitral valve. The elevation in INR was noted two weeks after the patient began to drink cranberry juice. Subsequent symptoms included postoperative bleeding problems. The bleeding was thought due to a biologically plausible interaction between the drug and the juice. It was concluded that patients taking warfarin should limit their cranberry juice intake.
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