St. Joseph Health System
Download iPhone App Visit our YouTube Channel Find us on Facebook Follow us on Twitter
Print    Email

All About Coumadin

What is Coumadin?
Coumadin is a blood thinner, also known as an anticoagulant. Coumadin is the name brand for the drug Warfarin. These are the same drug. It helps to prevent clots from forming in the blood. It works by blocking the formation of certain clotting factors.

Why do I need to take Coumadin?
Patients can be on Coumadin for several reasons. These include:

  • Atrial Fibrillation (heart beats rapidly and irregularly)
  • Replacement of certain valves in the heart
  • Deep Vein Thrombosis (clot in the arm or leg)
  • Pulmonary embolus (clot in the lungs)

If you have atrial fibrillation, blood is not being completely emptied from your heart with each beat. This blood that is left behind pools in the heart and can form a clot. If this happens and the clot breaks loose, it can travel up to the brain where it can lead to a stroke and possibly death.

If you have had certain valves replaced in your heart, the new valve material is different than your body's original valves. You need to be on Coumadin to prevent clots from forming on these new valves.

If you have had a clot form in your arm, leg, or lung, these clots have the potential to grow bigger or break loose. They can travel into the lungs or to the brain, which can cause a stroke.

How long do I have to be on Coumadin?
This depends on why you are on Coumadin as well as several other factors specific to each person. Your physician will discuss this with you.

How does Coumadin work?
Coumadin is a Vitamin K+ antagonist. This means it interferes with Vitamin K, a vitamin needed by the body to form clots.

What is an INR blood test?
While on Coumadin, it is important to check the level of Coumadin in your body regularly. This is checked through a test called a Protime or INR. The protime is used to find out how long it takes your blood to clot. The result is a number called an INR (International Normalizing Ratio). When your INR test is done here in our office, we will be adjusting your Coumadin dosage to keep your INR in the correct goal range for your condition. Your physician will decide on the goal that will be most appropriate for you.

Why is the INR test important?
If your INR is too high, then your blood will not clot fast enough. In other words, your blood is "too thin." This increases your chances of bleeding.

If you INR is too low, then your blood will clot easier. In other words, your blood is "too thick." This does not provide the protection you need from clots.

*INR testing is NOT a fasting lab*
Coumadin levels are checked frequently when you first start on Coumadin. As your INR stabilizes and it stays in your INR therapeutic range, your visits will be less
frequent and you will go to once a month testing.

What affects Coumadin levels?
There are many different things that can change your Coumadin levels, or make your INR higher or lower. It is important to be aware of these factors and keep a consistent lifestyle. Always inform the Coumadin Clinic of any changes.

  • Food with high levels of vitamin K lower your INR level
  • Dehydration: Fever, diarrhea, and exercise can cause dehydration. This causes a decrease in fluid volume in the body, which concentrates the Coumadin medication in your body. This will increase INR levels.
  • Alcohol consumption: This will increase your INR.
  • Herbal or Supplemental products: These will increase or decrease your INR.
  • Prescription and non-prescription drugs: The effect on your Coumadin level depends on the drug. Always call the Coumadin Clinic when you start or stop any of your meds. If you need an over-the-counter medication, please consult with your pharmacist who will tell you which medications do not interact with your Coumadin.


© 2015 St. Joseph Health System, Bryan, Texas   |   979-776-3777   |   Employee Email Access
A Ministry of Sylvania Franciscan Health