Dietary Restrictions For Green Tea & Coumadin

Green tea is used as a beverage, and some people also use it as an herbal medicine. Green tea may help prevent or treat low blood pressure, genital warts, Parkinson's disease, certain types of cancer and hyperlipidemia. The caffeine in green tea may also help keep you more alert. However, green tea can interact with certain medications, including Coumadin.

Coumadin Use

Coumadin, or warfarin, is a blood thinner that doctors prescribe to help prevent and treat blood clots. This can lower your risk for stroke or heart attack. However, while you are taking Coumadin, you need to watch your diet to keep the effects of this drug consistent. Doctors monitor your blood-clotting times while you are on Coumadin to make sure you are taking the proper dose.

Coumadin and Vitamin K

Because vitamin K also affects blood clotting, you need to keep your consumption of vitamin K consistent and avoid consuming too much vitamin K. This means you need to limit your intake of foods that are high in vitamin K. These include green leafy vegetables. Adult women should consume approximately 90 mcg per day of vitamin K and adult men 120 mcg per day, according to MayoClinic.com.

Green Tea and Coumadin

An April 1999 article published in "The Annals of Pharmacotherapy" reported that green tea may counteract the effects of warfarin. While taking Coumadin, you should limit your intake of green tea for two reasons. First, it can be high in vitamin K, and second, it is high in caffeine, both of which can interfere with warfarin.

Considerations

If you are taking warfarin, keep your intake of vitamin K-containing foods consistent. If you plan to make any dietary changes, consult your doctor to determine whether they will necessitate a change in your warfarin dosage. This includes adding green tea to your diet, especially if you do so in large amounts.