Food-warfarin interaction: facts and fictions

Abstract

Communicating facts to change patient perceptions is a very challenging task in pharmaceutical care, especially in the case of interaction between food and warfarin. This review article aims to present concepts and approaches for managing the problem of food interactions and warfarin from a literature review and from the authors’ experience. This article explains three important points i.e., 1) Evidence on interaction between food and warfarin exists but is limited and the quality is low. The food with greatest amount of empirical evidences classified as good evidence for an interaction leading to the increase of INR and risk of bleeding is cranberry, while that leading to the decrease of INR and the increase of thromboembolic risk is broccoli. 2) Asking questions is more important than their answers, i.e., pharmacists must take detailed patient history, identify the problems and use patient information to resolve the problems of individual patient. Appropriate thinking leads to effective pharmaceutical care. The decision-making should consider empirical medical evidence and be tailored to individual patient's response and 3) communication to achieve patient adherence to treatment plan must be concrete.