Anticoagulants are medicines that help prevent blood clots. Blood clots can lead to stroke. These medicines are often called blood thinners, but they don't actually thin your blood. Instead, they increase the time it takes for a blood clot to form.
Anticoagulants used for atrial fibrillation are warfarin (Coumadin), dabigatran (Pradaxa), and rivaroxaban (Xarelto).
Atrial fibrillation increases your risk of stroke. Taking an anticoagulant can reduce that risk.
The risk of stroke isn't the same for everyone who has atrial fibrillation. But on average, people who have atrial fibrillation are 5 times more likely to have a stroke than people who don't have atrial fibrillation.1 Anything that increases your risk for a disease or problem is called a risk factor. The more risk factors you have, the greater your chance of having a stroke.
Anticoagulants can help protect against stroke. Your doctor may recommend that you take an anticoagulant if you are at high risk for stroke based on your risk factors.
Risk factors for stroke (besides atrial fibrillation) include:
When you take an anticoagulant, your blood clots more slowly than normal. This increases your risk of bleeding problems in and around the brain, bleeding in the stomach and intestines, bruising and bleeding if you are hurt, and serious skin rash.
Some people can't take anticoagulants, because they have a higher risk of having a serious problem if bleeding occurs. Your own risk of bleeding may be higher or lower based on your health. For example, you may have a higher risk of bleeding if you have uncontrolled high blood pressure, have kidney or liver disease, or drink large amounts of alcohol.
When you take an anticoagulant, also called a blood thinner, you need to take extra steps to avoid bleeding problems, such as preventing falls and injuries. With the anticoagulant warfarin, you also need to have regular blood tests to make sure you are taking the right dose. And you need to watch how much vitamin K you eat or drink.
You will want to weigh the benefits of reducing your risk of stroke against the risks of taking an anticoagulant, such as an increased risk of bleeding. For example, each year about 1 to 3 out of 100 people (or 10 to 30 out of 1,000 people) who take an anticoagulant will have a problem with severe bleeding. This means that 97 to 99 out of 100 people (or 970 to 990 out of 1,000 people) will not have a bleeding problem.2, 3, 4, 5 But these are average risks. Your own risk may be higher or lower than average based on your own health.
Anticoagulants lower the risk of stroke in people who have atrial fibrillation. But how much your risk will be lowered depends on how high your risk was to start with. Not everyone with atrial fibrillation has the same risk of stroke. It's a good idea to talk with your doctor about your risk.
Aspirin may be a good choice if you are young and have no other heart or health problems or if you can't take an anticoagulant (blood thinner) safely. Aspirin doesn't work as well as an anticoagulant to reduce your stroke risk.6
If you are at low risk for stroke or can't take an anticoagulant, your doctor may recommend that you take aspirin. Aspirin is an antiplatelet medicine. It reduces the risk of blood clotting by preventing the smallest blood cells (platelets) from sticking together and making a clot.
Aspirin is less likely than an anticoagulant to cause bleeding problems. Bleeding that is bad enough to need treatment in a hospital happens in 1 or 2 out of 1,000 people who take aspirin.7 This means that 998 or 999 out of 1,000 people who take aspirin don't have serious bleeding.
Other antiplatelet medicines, such as clopidogrel (Plavix), may be used. Your doctor may have you take them with aspirin or instead of aspirin. When aspirin and clopidogrel are used together, they may reduce the risk for stroke more than aspirin alone. This combination of clopidogrel and aspirin doesn't work as well as an anticoagulant to prevent clots. This combination is also more likely to cause bleeding than aspirin alone.8
Your doctor may advise you to take an anticoagulant if:
|Take an anticoagulant to reduce the risk of stroke||Don't take an anticoagulant|
|What is usually involved?|
|What are the benefits?|
|What are the risks and side effects?|
Are you interested in what others decided to do? Many people have faced this decision. These personal stories may help you decide.
These stories are based on information gathered from health professionals and consumers. They may be helpful as you make important health decisions.
"I have other risk factors for stroke besides atrial fibrillation. My doctor and I decided that it is important for me to take a blood thinner to help reduce my risk for having a stroke."
— Monty, age 72
"I have a lot of balance problems. They might get better over time, but I do worry about falling. And my doctor says my stroke risk is low. I think I'll stick with aspirin for now."
— Juan, age 67
"I am not overly concerned about bleeding problems from taking a blood thinner, and I'm motivated to follow the instructions to take it as directed."
— Martha, age 64
"I have a bleeding ulcer that I am caring for, so I am not a good candidate for blood thinners."
— Geraldo, age 52
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 an anticoagulant
Reasons not to take an anticoagulant
I worry about my risk of stroke.
My risk of stroke is low.
I'm confident that I can take an anticoagulant as directed.
I'm worried that I can't take an anticoagulant as directed.
Lowering my risk of stroke is more important to me than the risk of a bleeding problem.
I'm more worried about my risk of a bleeding problem than my risk of stroke.
My other important reasons:
My other important reasons:
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.
Taking an anticoagulant
NOT taking an anticoagulant
1. If you have atrial fibrillation, are you at higher risk of stroke than someone who doesn't have it?
2. Are anticoagulants safe for everyone to take?
3. Does aspirin work as well as anticoagulants to reduce the risk of stroke?
1. Do you understand the options available to you?
2. Are you clear about which benefits and side effects matter most to you?
3. Do you have enough support and advice from others to make a choice?
1. How sure do you feel right now about your decision?
2. Check what you need to do before you make this decision.
3. Use the following space to list questions, concerns, and next steps.
|Primary Medical Reviewer||Rakesh K. Pai, MD, FACC - Cardiology, Electrophysiology|
|Specialist Medical Reviewer||John M. Miller, MD, FACC - Cardiology, Electrophysiology|
Fuster V, et al. (2011). 2011 ACCF/AHA/HRS focused update incorporated into the ACC/AHA/ESC 2006 guidelines for the management of patients with atrial fibrillation: A report of the American College of Cardiology Foundation/American Heart Association Task Force on Practice Guidelines. Circulation, 123(10): e269–e367.