Prevention and Treatment of Excessive Blood Clotting (Hypercoagulation)

While you can't prevent genetic causes of excessive blood clotting, you can take the following steps to reduce acquired risk factors, such as:

  • Treating conditions that can lead to excessive blood clotting, such as diabetes or heart and vascular diseases like PAD.
  • Quitting smoking and losing weight if needed.
  • Avoiding medicines that contain the female hormone estrogen. Ask your doctor about other safer options.
  • Staying active if you can. Moving your legs, flex, and stretching during long trips. This helps keep blood flowing in your calves.
  • Talking with your healthcare provider about ways to lower your homocysteine level if it's high. Your doctor may prescribe anticoagulants, or *blood thinners, before, during, and/or after surgery or medical procedures to prevent excessive blood clotting.


Excessive blood clotting is treated with medicines, but because blood clots can be dangerous, you may need emergency treatment.

Depending on the size and location of the clot(s), you may need emergency treatment or routine treatment.

  • Emergency Treatment - Blood clots can damage the body, leading to serious problems, such as stroke, heart attack, kidney failure, deep vein thrombosis or pulmonary embolism. They can also cause miscarriages, stillbirths, or pregnancy-related problems. Emergency treatment to prevent these problems often involves medicines called thrombolytics or "clot busters," that can quickly break up clots. These medicines can cause sudden bleeding so they're only used to break up large blood clots in life-threatening situations.
  • Routine Treatment - Blood Thinners. In a non-emergency situation, anticoagulants (PDF), or "blood thinners," are used to keep existing clots from getting larger and to prevent new clots from forming. 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 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 healthcare provider may treat you with both heparin and warfarin at the same time. Heparin acts quickly. Warfarin takes several days before it starts to work. Once the warfarin starts to work, the heparin is stopped.
  • Other Treatments - Short-term treatments may include antithrombin factor and protein C.
    • Antithrombin factor is used for people known to have antithrombin deficiencies and is often 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 that can destroy and damage skin cells.
* Some medications are commonly called blood thinners because they can help reduce a blood clot from forming. There are two main types of blood thinners that patients commonly take: anticoagulants such as warfarin, dabigatran (Eliquis) and rivaroxaban (Xarelto), and antiplatelet drugs such as aspirin or clopidogrel. Each type of medication has a specific function to prevent a blood clot from forming or causing a blocked blood vessel, heart attack or stroke. 

The American Heart Association receives support from pharmaceutical and biotech companies, device manufacturers and health insurance providers whose products may be mentioned in this article. The American Heart Association maintains strict policies preventing supporters from influencing science-based health information. A list of supporters can be found here.