dietary interactions with warfarin

Foods that contain significant amounts of vitamin K can interfere with the anticogulant effect of warfarin - green leafy vegetables - green tea - soy High-protein, low-carbohydrate diets such as Atkins & South Beach diet may lower INR via - an increase albumin, which in turn binds warfarin - enhancing warfarin metabolism Cranberries contain flavonoids that may inhibit cyt P450 2C9 & warfarin metabolism, thus increasing warfarin's effect Garlic has antiplatelet properties & may increase risk of bleeding in patients taking warfarin Alcohol 1) > 2 drinks/day can increase INR in most people 2) chronic alcohol abuse tends to diminish INR Grapefruit inhibits cyt P450 3A4 thus may inhibit warfarin metabolism > 24 ounces of grapefruit juice daily may increase INR

References

Prescriber's Letter 12(5): 2005 What You Should Know About Your Diet and Warfarin Detail-Document#: 210507 (subscription needed) http://www.prescribersletter.com