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What do I need to know about anticoagulants?

        Health | Heart

Anticoagulants are sometimes called blood thinners. They slow down the clotting of your blood in your arteries and veins.

When are anticoagulants prescribed?

When you have CHD, your doctor may prescribe anticoagulants to help prevent blood clots from forming in your heart. Your doctor may also use these medicines after a heart attack to prevent any clots from further cutting off the blood supply to your heart. They are also used to prevent blood clots in people who have atrial fibrillation, which is a rapid heartbeat.

Common Names of Anticoagulants

The following table lists some common brand and generic names for anticoagulants.


brand generic
Coumadin warfarin sodium
Dicumarol dicumarol
Fragmin dalteparin sodium
Lovenox enoxaparin sodium
Miradon anisindione
Normiflo ardeparin sodium
Orgaran

danaparoid sodium


How Anticoagulants Work

Anticoagulants increase the time it takes the blood to clot. This prevents harmful clots from forming and blocking blood flow. They can also prevent existing clots from getting bigger. They cannot dissolve existing clots.

Precautions and Possible Side Effects of Anticoagulants

Precautions to take when you are on anticoagulants:

  • Check with your doctor to see how often you need to have your blood checked. It is necessary to have your blood checked frequently when you are on some types of anticoagulants.
  • Avoid taking aspirin unless your doctor tells you otherwise.
Possible side effects of anticoagulants that you may notice:
  • abdominal cramps
  • bruising
  • dizziness
  • fever
  • severe headache
  • stroke from bleeding into the brain
  • vomiting

If you are taking one of these medicines, be sure to report any bleeding to your doctor immediately. This would include blood in your urine or stool or nosebleeds. Also, let your doctor know if you have any of the following signs that may indicate severe bleeding:

  • difficulty breathing or swallowing
  • unexplained pain in your chest, abdomen, joint, muscles, or elsewhere
  • unexplained swelling
  • weakness

Possible side effects of anticoagulants that you may not notice: Although you may not be aware that your body is experiencing any of the following changes, your doctor will be able to test for these side effects during an office visit. Be sure to keep all follow-up appointments with your doctor.

  • bleeding into tissues or organs
  • low blood pressure

Possible Drug Interactions with Anticoagulants

Unless your doctor tells you to do so, do not take anticoagulants with antiplatelets. Aspirin is a common antiplatelet. When these types of medicines are combined, the blood can become too thin. This can cause uncontrolled bleeding. Also, avoid anti-inflammatory medicines and alcohol if you are on this type of medicine. If you take coumadin, do not eat large amounts of food rich in vitamin K. Examples of food rich in vitamin K include:

  • cabbage
  • vegetable oil, such as canola and soybean
  • green leafy vegetables
  • mayonnaise
Vitamin K can cancel out the effects of anticoagulant medicine.

Other foods and drugs may have an effect on anticoagulants too. Always tell your doctor about all the medicines that you take. Do not use any other medicine without your doctor's okay. This includes:

  • prescription medicines ordered by another doctor
  • over-the-counter medicines
  • herbal remedies
  • vitamins and minerals

It's best to keep an updated list of these and bring a copy to give to your doctor. That way you can add to it whenever you take something new or delete the types you no longer take. Make a copy for each of your doctors so that they can keep it in your file. This complete list helps your doctor be better prepared to prescribe an anticoagulant that is the least likely to interact with your other treatments.


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