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Medications and Diet



Use of Medications


It is very important to talk with your doctor about all of the other medicines that you are taking, including over-the-counter medicines, antibiotics, vitamins, or herbal products. When Coumadin®/Warfarin is taken with other medicines, it can change the way other medicines work. Other medicines can also change the way Coumadin®/Warfarin works.


Any product containing aspirin may lessen the blood’s ability to form clots and may harm you when you take Coumadin®/Warfarin. If you take a daily aspirin, talk with your doctor about what dose is right for you. Other medicines you get over-the-counter may have aspirin in them. All medications must be approved by your doctor, including medicines you have taken before you started Coumadin®/Warfarin. Following is a list of some common medications that should be approved by your doctor.

Pain Relievers
Stomach Remedies
Herbal Products
  • Excedrin®
  • Acetaminophen (Tylenol®)
  • Naproxen (Aleve®)
  • Ibuprofen (Advil®, Motrin®, Nuprin®, Midol®, Pamprin HB®)
  • Cimetidine (Tagamet HB®)
  • Bismuth Subsalicylate (Pepto Bismol®)
  • Laxatives and stool softeners
  • Alka-Seltzer®
  • Garlic
  • Green Tea
  • Ginkgo
  • Vitamins


Check the Coumadin®/Warfarin you are taking.

  • Does the medicine seem different from what your doctor wrote on the prescription or look different from what you expected?

  • Does your refill look different than what you used before?

  • Is the color the same as what you were previously given?

If something seems different, ask the pharmacist to double-check it. Most errors are first found by patients.
Check your medicine.

Always tell your doctor about all the medicines you are taking. Tell your doctor when you start taking new medicine and when you stop. Bring a list of current medications, over-the-counter drugs—such as aspirin—and any vitamins and herbal products you take.



Diet for Coumadin®/Warfarin Users

The foods you eat can affect how well Coumadin®/Warfarin works for you. High amounts of vitamin K might work against Coumadin®/Warfarin. Talk to your doctor about the amount of vitamin K that is right for you.



These foods contain vitamin K

Fruits and Vegetables
Oils and Nuts
  • Kiwi
  • Blueberries
  • Broccoli
  • Cabbage
  • Brussels sprouts
  • Green onions
  • Asparagus
  • Cauliflower
  • Peas
  • Lettuce
  • Spinach
  • Turnip, collard, and mustard greens
  • Parsley
  • Kale
  • Endive
  • Mayonnaise
  • Margarine
  • Canola oil
  • Soybean oil
  • Vitamins
  • Soybeans
  • Cashews B®)
  • Beef liver
  • Pork liver

Do not make any major changes in your diet or start a weight loss plan without calling your doctor.

Call your doctor if you are unable to eat for several days, for whatever reason. Also call if you have stomach problems, vomiting, or diarrhea that lasts more than 1 day. These problems could affect your Coumadin®/Warfarin dosage.

Limit your consumption of alcohol.
Alcohol can affect your Coumadin®/Warfarin dosage, but it does not mean you must avoid all alcohol. Serious problems can occur with alcohol and Coumadin®/Warfarin when you drink more than 2 drinks a day or when you change your usual pattern. Binge drinking is not good for you. Be careful on special occasions or holidays, and drink only what you usually would on any regular day of the week.

To download a copy of the entire brochure, click here. [PDF]
From Blood Thinner Pills: Your Guide to Using Them Safely by the Agency for Healthcare Research and Quality (AHRQ)