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Medications specifically to prevent clots forming and to reduce your stroke risk

The most common cause of stroke is a blood clot – which if you have AF, can start inside your heart and be pumped through your body. If this clot reaches your brain it can cause a stroke.

There are treatments to prevent clots forming inside your heart. These are called anticoagulants and antiplatelets.1 They help reduce stroke risk by helping to prevent blood from ‘coagulating’ or clotting.1 This is why they are usually an important part of the long-term medical treatment for people who have AF. It’s important to bear in mind that more medications are becoming available all the time.

Here is an overview of the options your doctor has in stroke prevention for AF patients, like you.1,2 Naturally everyone is different and your doctor may adjust the medication you are offered to suit your individual requirements.

Direct thrombin inhibitors (DTI)

  • The body produces a key coagulation element – an enzyme called thrombin, which it uses to trigger the formation of clots. These medications inhibit thrombin leading to the prevention of clot formation.
  • Regular blood tests are not needed because anticoagulation level is predictable and not affected by what you eat – direct thrombin inhibitors (DTI) are also less likely to be affected by other medication you might be taking.

Vitamin K antagonists (VKA) (warfarin)

  • There are four essential blood clotting factors which rely on vitamin K to allow the blood to clot. Unlike direct thrombin inhibitors (DTI), vitamin K antagonists inhibit the body’s production of these four factors, preventing clot formation.
  • Regular blood tests are needed to make sure that warfarin is working and that the dosage is correct for the protection you need. Warfarin can be affected by what you eat and is more likely to be affected by other medication you might be taking.

Acetylsalicylic Acid (ASA), e.g. aspirin 

  • Platelets play an essential role in the clotting system. ASA inhibits the platelet function, reducing clot formation.
  • Given to the minority of patients where warfarin is not appropriate and other effective alternatives, such as direct thrombin inhibitors (DTI), are not available. It is less effective treatment option in AF related stroke prevention.

Factor Xa Inhibitors

  • Factor Xa (FXa) plays a key role in the clotting process by converting prothrombin to thrombin. Thrombin is needed for blood clot formation.
  • Factor Xa inhibitors block FXa from doing its job and this interrupts the clotting process. There are two types of Factor Xa inhibitor that block FXa either directly or indirectly. These are called:
  • Direct Factor Xa inhibitors
  • Indirect Factor Xa inhibitors

    As part of your treatment plan, your doctor may also address other factors such as high blood pressure, high cholesterol, diabetes, or a history of previous stroke or transient ischemic attack (TIA – an important predictor of stroke) and treat these conditions appropriately to help bring them under control. There may also be trigger factors such as being overweight and smoking that your doctor may be able to help you with too.

    If you have been diagnosed with AF, don’t wait. Talk to your doctor about how to help reduce your stroke risk today. Only you and your doctor can determine the treatment plan that is right for you.

    Possible anticlotting side effects

    Taking an anticlotting agent makes you bleed more easily. If you fall or bump your head, call your doctor or emergency services immediately because you could suffer from internal bleeding without showing any sign of this externally.3

    Top tips to avoiding unnecessary bleeding3

    Using a garden trowel to plant  

  • Take care when using knives, scissors, nail clippers, or any sharp objects
  • Use an electric razor, if possible
  • Gums can bleed too—use a soft toothbrush and waxed dental floss. Don’t use toothpicks. Be sure to tell your dentist you are taking an anticlotting agent before any procedure, including a cleaning
  • Wear gloves when gardening or using sharp tools
  • Do not trim corns or calluses yourself
  • Prevent falls, ensure stairways and floor space is free from clutter, mop up kitchen spills as soon as they happen4

1. Atrial fibrillation drug information. Atrial Fibrillation Society. February 2011.
2. Mureebe L. Direct thrombin inhibitors. Accessed 9 May 2011.
3. Agency for Healthcare Research and Quality. Blood thinner pills: your guide to using them safely. Accessed 9 May 2010.
4. Accessed 17 May 2011