What should I know about Coumadin before taking it?

The following are some guidelines when taking Coumadin:
  • You'll need to have regular blood tests, called PT (or PT/INR) tests. These tests tell your healthcare provider if your blood is clotting to the right level.
  • Avoid drastic changes in your diet. It's especially important to be consistent in the amount of dark green, leafy vegetables (like spinach) you eat from day to day. These vegetables are important for your health. They are also high in vitamin K, which affects how Coumadin works. Eat about the same amount of them each day so your Coumadin levels stay consistent.
  • Limit cranberry juice to 1/2 cup (4 ounces) per day. Drinking more than 1/2 cup of cranberry juice can affect how Coumadin works in your body.
  • Your doctor may also tell you to avoid drinking grapefruit juice at the same time you take Coumadin (doctor advice varies).
  • Talk to your provider before taking aspirin or arthritis medication.
  • Call your healthcare provider if you notice bleeding from your gums or blood in your urine or stools.

Before taking Coumadin, talk to your doctor about the risk of severe bleeding. Older persons are more at risk for bleeding problems. You should seek immediate medical help if you show signs of abnormal, excessive or internal bleeding. You may be given blood tests to see how you will respond to Coumadin and what your dosage should be.

You should not take this medication if you are pregnant or breast-feeding. Tell your doctor if you have recently had a severe injury or bleeding problems. It is very important that you tell your doctor about all of the medications you are currently taking, including prescriptions, over-the-counter medications and supplements. Many drugs can interact with Coumadin, including antibiotics; aspirin; nonsteroidal anti-inflammatory drugs (NSAIDs); heparin; medications for cancer, cholesterol, colds and allergies, depression, diabetes, digestive problems, heart disease, mental illness, pain, seizures, thyroid problems and tuberculosis; oral contraceptives (birth control pills); streptokinase; ticlopidine; and urokinase. This is not a complete list.

Some supplements that can interact with Coumadin include: bromelains, coenzyme Q10, cranberry, danshen, dong quai, garlic, ginkgo biloba, ginseng, St. John's Wort and vitamin K. Avoid making any changes in your diet without first talking to your doctor.  Follow your doctor's specific instructions on taking medications and your diet while receiving treatment with Coumadin.  

Continue Learning about Anticoagulant

How can anticoagulants affect oral surgery?
American Dental AssociationAmerican Dental Association
Reduced blood clotting is a side effect of aspirins and anticoagulants, such as heparin or warfa...
More Answers
What does it mean if my mother's PT/INR test result is too high?
Stacy Wiegman, PharmDStacy Wiegman, PharmD
If your mother's PT/INR test result is too high, it means that her dose of warfarin is too high,...
More Answers
How are anticoagulants used?
Anticoagulants are medications that inhibit blood clotting. While they cannot dissolve an existing c...
More Answers
What is an anticoagulant?
Brigham and Women's HospitalBrigham and Women's Hospital
An anticoagulant (anti means against, and coagulant refers to blood clotting) or "blood thinner"...
More Answers

Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.