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Get in Rhythm. Stay in Rhythm.® Atrial Fibrillation Patient Conference October 30 - November 1, 2020, in Dallas, TX
Get in Rhythm. Stay in Rhythm.® Atrial Fibrillation Patient Conference October 30 - November 1, 2020, in Dallas, TX

Anticoagulant Medication for Atrial Fibrillation

Anyone with atrial fibrillation is at a very high risk of stroke. Thus anticoagulant medication, also called a blood thinner, is the most common medication used in managing atrial fibrillation. As an afib patient, you are probably on a blood thinner.

When the blood pools in the atria due to an irregular heartbeat from atrial fibrillation, the risk of blood clot formation increases. Anticoagulants decrease that risk by reducing the potential of blood clot formation. Anticoagulants reduce the risk of ischemic stroke by 68 percent, 1 and are recommended regardless of whether you are on rate control medication or rhythm control medication. 2

The body protects you when you get a cut because the blood contains clotting proteins that cause your blood to clot. Vitamin K regulates the creation of these clotting proteins. Anticoagulants work by disrupting the body's Vitamin K levels, decreasing the body's production of clotting proteins and thus the propensity to form clots.

If you need anticoagulants, you will receive warfarin, which is the generic, or Coumadin®, which is the brand name. Coumadin® was originally created as a rat poison (rodenticide), so while you are on it you can expect to hear jokes about taking rat poison.

Those jokes would be more amusing if Coumadin® weren't such a nasty and difficult drug. For some Coumadin® patients, and perhaps even for you, Coumadin® is a nightmare because you are unable to maintain control and keep your vitamin K levels stable.

Risks from Coumadin®

Vitamin K helps to maintain bone strength so those on Coumadin® are at increased risk of bone fractures, particularly in the elderly. Other risks include headaches, dizziness, and very rarely, skin necrosis.

The major risk from Coumadin®, however, is bleeding. The US Food and Drug Administration (FDA) has issued a black box warning that warfarin (Coumadin®) poses a serious and significant health risk due to the potential for major, or even fatal, bleeding.

Because of this, if you are on Coumadin®, consider wearing Medic Alert jewelry at all times and informing medical and dental personnel that you are on Coumadin®. Also, family and friends should be aware of what to do if you have a Coumadin® emergency.

Life on Coumadin®

While Coumadin® works for some patients, it doesn't work for all. This medication regimen is sometimes difficult to manage, requiring consistency in dosage and diet along with constant blood monitoring and curtailing of many normal activities. It often has nasty side effects as well. For some of us, Coumadin® is life-changing, and not in a good way.

What makes Coumadin® so difficult? It's necessary to keep your blood thickness within a very tight range, which is measured through a blood test called Protime. It measures your blood thickness on a scale that is called an International Normalized Ratio (INR). Your INR should stay between 2.0 and 3.0, with 2.5 being ideal. If it's less than 2.0, your blood is too thick and you have the risk of blood clots and stroke. If it's above 3.0, your blood is too thin and you have the risk of bleeding to death.

One factor that greatly influences your INR and stability on Coumadin® is diet. What you eat can dramatically change your INR almost immediately. Doctors say to eat exactly the same thing in the same quantities at the same time every day. As a practical matter, that's very difficult to do.

Green vegetables and some other foods, including olives, olive oil, some nuts, and some legumes, are major sources of vitamin K. Knowing what foods contain vitamin K is important if you are on Coumadin®. Keeping vitamin K stable is a key to maintaining a stable INR.

Thus, if you eat green vegetables, as you should, you must eat the same amount of the same ones every day, whether at home, at work, or traveling. That's not always easy to do, especially if you travel. Your daily dosage of Coumadin® is based on what you need to keep your INR stable, and once stable, theoretically you can continue to eat the same amount of the same things and remain stable. It doesn't always work that way.

You should also avoid some herbs, such as ginseng, gingko biloba, ginger, garlic, and St. John's Wort, which can interfere with Coumadin®.

For patients such as our founder, Mellanie True Hills, living on Coumadin® was challenging and life-changing as it was impossible to keep Coumadin® under control no matter how she managed her diet.

If you're stable, monthly blood draws are sufficient, but being unstable means weekly blood draws, whether you are at home or on the road. Your dosage is tweaked based on each week's test results as you ping-pong between the risk of clots and bleeding.

If your blood is too thin it leaks from the blood vessels and leaves huge black, blue, and purple bruises all over arms, legs, torso, and even your face. Just being touched or bumped leaves nasty bruises. Mellanie's family was embarrassed to take her anywhere looking like that.

Activities are severely restricted, too-no yard work, no kitchen knives, no shaving-to avoid getting scratched or cut. It may mean stopping favorite sports or hobbies.

Mellanie was grounded and couldn't fly. The risk of traveling alone, even driving just an hour away, was too great. Her family traveled with her, and they knew all the hospitals along their route.

When a research study came out that indicated that one-fourth of warfarin (Coumadin®) patients aren't stable for genetic reasons, she knew that this nightmare couldn't continue for the rest of her life. That was a huge motivator in her quest for an afib cure.

For more information about afib cures, see Can Afib Be Cured?

1 Russo, Andrea M., MD, "Overview of the Contemporary Evaluation and Management of Patients with Atrial Fibrillation: What Every General Practitioner Should Know" <
>, American Heart Association [Internet], Copyright, 2006.

2 Wyse, D. George, M.D., "Rate Versus Rhythm Control in the Management of Atrial Fibrillation" <
>, American Heart Association [Internet], Copyright, 2006.

Last Modified 12/23/2008

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