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decision pointAtrial Fibrillation: Which Anticoagulant Should I Take To Prevent Stroke?

Your options

  • Take warfarin to prevent stroke.
  • Take dabigatran to prevent stroke.

Is this decision for you? This could be a decision for you if you are newly diagnosed with atrial fibrillation or if you are already taking warfarin. You may first want to decide whether to take an anticoagulant at all.

Key points to remember

  • Atrial fibrillation increases your risk of stroke. Taking either warfarin (Coumadin) or dabigatran (Pradaxa) lowers that risk.
  • Warfarin has been used for many years to reduce the risk of stroke in people with atrial fibrillation. The medicine is low-cost, and doctors understand its long-term side effects.
  • Dabigatran is a newer medicine that also lowers the risk of stroke. It works as well as warfarin, but it costs more. It may be a good choice if you cannot take warfarin safely.
  • When you take warfarin, you need to have regular blood tests to make sure that you are taking the right dose. And you need to watch how much vitamin K you eat and drink. With dabigatran, there are no regular blood tests and you don't have to watch your vitamin K intake.
  • Both medicines work by increasing the time it takes for a blood clot to form, so they increase your risk of problems from bleeding. Whether you take warfarin or dabigatran, you need to be careful to avoid serious bleeding by preventing falls and injuries.

How do anticoagulants lower your risk of stroke?

Atrial fibrillation increases your risk of stroke. The risk of stroke isn't the same for everyone who has atrial fibrillation. But people who have atrial fibrillation are 5 times more likely to have a stroke than are people who don't have atrial fibrillation.1

Taking an anticoagulant such as warfarin (Coumadin) or dabigatran (Pradaxa) lowers that risk. These medicines are also called blood thinners, but they don't really thin your blood. Instead, they increase the time it takes for a blood clot to form.

How are these medicines the same?

Lowering risk of stroke

Warfarin and dabigatran work about the same to lower your risk of stroke if you have atrial fibrillation.2

Raising risk of bleeding

Anticoagulants make your blood clot slower than normal. Both warfarin and dabigatran increase your risk of bleeding problems in and around the brain, bleeding in the stomach and intestines, and bruising and bleeding if you are hurt. So when you take either medicine, you need to take extra care to prevent bleeding, such as preventing falls and injuries.

The risks of bleeding are about the same for warfarin and dabigatran. Each year about 2 out of 100 people who take warfarin will have a problem with severe bleeding, and 98 will not.3 And each year about 3 out of 100 people who take dabigatran have a problem with severe bleeding, while 97 do not.2 Your own risk of bleeding may be higher or lower than average, based on your own health. Ask your doctor to help you understand your risk.

Some people can't take warfarin or dabigatran, because they have a higher risk of having a serious problem if bleeding occurs. You shouldn't take these drugs if:

  • You have blood in your stool for no clear reason.
  • You can't control your blood pressure.
  • You drink large amounts of alcohol.

Let your doctor know if you are scheduled for any procedure that raises your risk of bleeding. Your medicine may need to be adjusted.

How are these medicines different?

Taking warfarin

Warfarin has been used for many years to reduce the risk of stroke in people who have atrial fibrillation. The medicine is low-cost, and doctors understand its long-term effects. How much your risk will be reduced when you take warfarin depends on how high your risk was to start with.

When you take warfarin, you'll need to get regular blood tests to make sure you are taking the right dose. And you will need to watch how much vitamin K you eat and drink.

Warfarin may cause birth defects and problems if you take it while you are pregnant.

Taking dabigatran

Dabigatran is a newer anticoagulant. Its long-term effects aren't known. It works slightly better than warfarin at preventing stroke.2 But like warfarin, how much your risk will be reduced depends on how high your risk was to start with. You don't need to have regular blood tests or watch your vitamin K intake with dabigatran.

You can't take dabigatran if you have heart valve disease, an artificial heart valve, or severe kidney or liver disease.4 Doctors don't know how dabigatran will affect you if you take it while you are pregnant.

Cost

Dabigatran costs about $3000 for a 1-year supply. Warfarin costs about $48 for a 1-year supply. If you have health insurance, some or all of this cost may be covered.5

Surgery

Doctors know how to monitor warfarin and how to reverse its effects if you need surgery. Since dabigatran is newer, doctors still don't know about long-term side effects. If you are taking dabigatran and need surgery, it may take longer to reverse the blood-thinning effects.

Why might your doctor recommend taking either warfarin or dabigatran?

Your doctor may recommend that you take or stay on warfarin if:

  • You have heart valve disease, an artificial heart valve, or severe kidney or liver disease. You can't take dabigatran if you have these health problems.
  • You are already taking warfarin and aren't having any problems keeping a safe level of medicine in your blood.

Your doctor may recommend that you try dabigatran if:

  • You've been taking warfarin and have problems keeping a safe level of medicine in your blood.
  • You are already taking warfarin and are having a problem with side effects.
  • You are able to take dabigatran twice a day as directed.
Take warfarin to prevent stroke Take warfarin to prevent stroke

What is usually involved?

  • You take a pill once a day.
  • You have regular blood tests to make sure you are taking the right dose.
  • You take extra care to avoid bleeding by preventing falls and injuries.
  • You let your doctor know about any new medicines you start taking while you are taking warfarin.

What are the benefits?

  • Warfarin has been used for many years to reduce the risk of stroke in people who have atrial fibrillation.
  • It is low-cost. A 1-year supply of warfarin costs about $48.5
  • If you need surgery or if you have serious bleeding, the blood-thinning effects of warfarin can be reversed.

What are the risks and side effects?

  • Warfarin increases your risk of bleeding problems.
  • Side effects include skin rash.
  • You need to be careful about how much vitamin K you eat and drink.
  • Warfarin may cause birth defects if you take it while you are pregnant.
  • Warfarin lowers your risk of stroke, but you could still have a stroke.
Take dabigatran to prevent stroke Take dabigatran to prevent stroke

What is usually involved?

  • You take a pill twice a day.
  • You take extra care to avoid bleeding by preventing falls and injuries.
  • You let your doctor know about any new medicines you start taking while you are taking dabigatran.

What are the benefits?

  • Dabigatran lowers the risk of stroke in people who have atrial fibrillation. It works slightly better than warfarin.2
  • You don't need regular blood tests from your doctor.
  • You don't need to watch how much vitamin K you eat.

What are the risks and side effects?

  • Dabigatran increases your risk of bleeding problems, especially stomach bleeding.
  • Side effects include stomach upset and stomach pain.
  • It can be expensive. A 1-year supply of dabigatran costs $3000.5
  • The long-term side effects of dabigatran are not known. Doctors don't know if dabigatran will affect you if you are pregnant.
  • If you need surgery or have a serious bleed, the blood-thinning effects of dabigatran can be hard to reverse.
  • Dabigatran lowers your risk for stroke, but you could still have a stroke.

Personal stories

Are you interested in what others decided to do? Many people have faced this decision. These personal stories may help you decide.

Your personal feelings are just as important as the medical facts. Think about what matters most to you in this decision, and show how you feel about the following statements.

Reasons to take warfarin

Reasons to take dabigatran

I don't mind watching how much vitamin K I eat and drink.

I don't want to have to track my vitamin K intake.

More important
Equally important
More important

I'd rather take a familiar medicine with a long record of use, like warfarin.

I'm comfortable taking a newer medicine, like dabigatran.

More important
Equally important
More important

I don't mind going to the doctor for regular blood tests.

I don't want to have to take regular blood tests.

More important
Equally important
More important

I can only keep track of taking one pill a day.

I can remember to take a pill twice a day.

More important
Equally important
More important

I prefer to take a less expensive medicine.

I'm not worried about the cost of my medicine.

More important
Equally important
More important

My other important reasons:

My other important reasons:

More important
Equally important
More important

Now that you've thought about the facts and your feelings, you may have a general idea of where you stand on this decision. Show which way you are leaning right now.

Take warfarin

Take dabigatran

Leaning toward
Undecided
Leaning toward

Check the facts

Do both kinds of medicine lower your risk of stroke?

  • Yes That's right. Both medicines can lower your risk of stroke if you have atrial fibrillation.
  • No Sorry, that's not right. Both medicines can lower your risk of stroke if you have atrial fibrillation.
  • I'm not sure It may help to go back and read "Get the Facts." Both medicines can lower your risk of stroke if you have atrial fibrillation.

Do I need to have regular blood tests if I'm taking dabigatran?

  • Yes Sorry, that's not right. With dabigatran, there are no regular blood tests. If you take warfarin, it's important to have regular blood tests to make sure that your medicine is working the way it should.
  • No That's right. With dabigatran, there are no regular blood tests. But if you take warfarin, it's important to have regular blood tests to make sure that your medicine is working the way it should.
  • I'm not sure It may help to go back and read "Get the Facts." With dabigatran, there are no regular blood tests. But if you take warfarin, it's important to have regular blood tests to make sure that your medicine is working the way it should.

Do both medicines increase your risk of bleeding?

  • Yes That's right. Both medicines increase your risk of bleeding, so it's important to take care to prevent falls and injuries.
  • No Sorry, that's not right. Both medicines increase your risk of bleeding, so it's important to take care to prevent falls and injuries.
  • I'm not sure It may help to go back and read "Get the Facts." Both medicines increase your risk of bleeding, so it's important to take care to prevent falls and injuries.

Decide what's next

Do you understand the options available to you?

Are you clear about which benefits and side effects matter most to you?

Do you have enough support and advice from others to make a choice?

Certainty

How sure do you feel right now about your decision?

Not sure at all
Somewhat sure
Very sure

Check what you need to do before you make this decision.

  • I'm ready to take action.
  • I want to discuss the options with others.
  • I want to learn more about my options.

Use the following space to list questions, concerns, and next steps.

Personal stories about taking warfarin and dabigatran

These stories are based on information gathered from health professionals and consumers. They may be helpful as you make important health decisions.

I live on a ranch more than 100 miles from my doctor's office. I don't plan on checking in with him every month to have my blood tested. So I'm going to try a blood thinner that doesn't need regular blood testing.

Chuck, age 48

I've been taking warfarin for a long time. I guess I'm just used to it. I haven't had any problems with it. I think I'll just keep taking it.

Maria, 70

The high cost of medicines is a concern. But I'd rather pay more and not have to watch what I eat or go to the doctor so often. I think I'll try dabigatran.

Jane, 59

I'm already taking a lot of different medicines. I don't know if I could remember to take two pills at different times of the day on top of all that. Also, I like knowing that my doctor is checking my blood regularly. I think I'll try warfarin first and see how it works.

Javier, 66

  • Atrial Fibrillation
  • Atrial Fibrillation: Should I Take an Anticoagulant to Prevent Stroke?

Citations

  1. Prevention of stroke in patients with atrial fibrillation (2009). Medical Letter on Drugs and Therapeutics, 51(1313): 41.

  2. Connolly SJ, et al (2009). Dabigatran versus warfarin in patients with atrial fibrillation. New England Journal of Medicine, 361(12): 1139-1151.

  3. Antiplatelet and anticoagulant drugs (2008). Treatment Guidelines From The Medical Letter, 6(69): 29-36.

  4. Wann LS, et al. (2011). 2011 ACCF/AHA/HRS focused updated on the management of patients with atrial fibrillation (update on dabigatran): A report of the American College of Cardiology Foundation/American Heart Association Task Force on Practice Guidelines. Circulation, 123(10): 1144-1150.

  5. Avorn J (2011). The relative cost-effectiveness of anticoagulants: Obvious, except for the cost and the effectiveness. Circulation. Published online May 23, 2011 (doi:10.1161/circulationaha.111.030148).

By Healthwise Staff
Primary Medical Reviewer Rakesh K. Pai, MD, FACC - Cardiology, Electrophysiology
Primary Medical Reviewer Adam Husney, MD - Family Medicine
Specialist Medical Reviewer Theresa O'Young, PharmD - Clinical Pharmacy
Last Revised August 19, 2011

WebMD Medical Reference from Healthwise

Last Updated: August 19, 2011
This information is not intended to replace the advice of a doctor. Healthwise disclaims any liability for the decisions you make based on this information.

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