Excessive blood clotting is treated with medicines. Depending on the size and location of the clot(s), you may need emergency treatment or routine treatment.
Blood clots can be dangerous. They can damage the body and lead to serious problems, such as stroke, heart attack, kidney failure, deep vein thrombosis, or pulmonary embolism. Blood clots also can cause miscarriages, stillbirths, or pregnancy-related problems.
Emergency treatment to prevent these problems often involves medicines that can quickly break up clots.
These medicines, called thrombolytics or "clot busters," are used to treat large clots that cause severe symptoms. These medicines can cause sudden bleeding. Thus, they're used only in life-threatening situations.
Anticoagulants, or "blood thinners," are used as routine treatment for excessive blood clotting. These medicines prevent blood clots from forming. They also keep existing blood clots from getting larger.
Blood thinners are taken as either a pill, an injection under the skin, or through a needle or tube inserted into a vein (called intravenous, or IV, injection).
Warfarin and heparin are two types of blood thinners. Warfarin is given in pill form. (Coumadin® is a common brand name for warfarin.) Heparin is given as an injection or through an IV tube.
Your doctor may treat you with both heparin and warfarin at the same time. Heparin acts quickly. Warfarin takes 2–3 days before it starts to work. Once the warfarin starts to work, the heparin is stopped.
Pregnant women are treated with heparin because warfarin can harm the fetus.
Sometimes aspirin is used with warfarin. Other times, aspirin might be used alone. Aspirin also thins the blood and helps prevent blood clots.
Some people have to take blood thinners for the rest of their lives if their risk of forming blood clots remains high.
Side effects. The most common side effect of blood thinners is bleeding. This happens if the medicine thins your blood too much. This side effect can be life threatening. Bleeding can occur inside your body (internal bleeding) or underneath your skin or from the surface of your skin (external bleeding).
Know the warning signs of bleeding, so you can get help right away. They include:
A lot of bleeding after a fall or injury or easy bruising or bleeding also might mean that your blood is too thin. Call your doctor right away if you have any of these signs.
People who are treated with blood thinners usually need regular blood tests called PT and PTT tests to check how well their blood is clotting.
These tests also show whether you're taking the right amount of medicine. Your doctor will check to make sure that you're taking enough medicine to prevent clots, but not so much that it causes bleeding.
Short-term treatments may include treatment with antithrombin factor and protein C. Antithrombin factor might be helpful for people who have known antithrombin deficiencies. This treatment is used in special situations, such as before surgery if there's a very serious blood clot or repeat blood clots.
Some people who have antithrombin deficiencies may need this treatment because heparin doesn't work for them.
Protein C might be given to people who have protein C deficiencies before they receive warfarin. Protein C is given to protect them from skin necrosis—a serious side effect of warfarin. (Skin necrosis destroys and damages the skin cells.)
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