Drugs to Treat Blood Clots in the Veins - Clot Busters

What are clot busters?

Clot busters (thrombolytics) are a type of medication used to dissolve blood clots. In most cases your body can break down and reabsorb a DVT blood clot on its own. However, your doctor may use clot busters to speed up this process if you have a large clot that is causing heart or breathing problems. Because clot busters increase the risk of dangerous bleeding, they will only be used when absolutely necessary.

The most common type of clot-busting drug used to treat DVT or PE is called tissue plasminogen activator (tPA), but other medications may also be used. tPA is also used to break up clots that caused a blocked-vessel stroke or heart attack.

See also: Immediate Stroke Treatment: tPA

How are clot-busters given?

Clot busters are usually given as an injection in the hospital. In some cases, the medication may be injected directly onto the clot during a procedure called catheter-directed thrombolysis. In this procedure, a long, thin tube called a catheter is inserted into a small cut in your groin or arm and guided through your blood vessels to the location of the clot using X-ray images. Once in place, the clot-busting drug is released onto the clot to dissolve it and restore blood flow. To learn more about the catheterization procedure, see cardiac catheterization.

Who might need clot busters to treat DVT or PE?

For most women with DVT or PE, blood-thinning drugs (such as LMWH) are enough to prevent further blood clots and reduce the risk of dying. However, some women with large blood clots, especially those that have broken off to block an artery in the lungs ( pulmonary embolism) may benefit from clot busters to speed the breakdown of the clot.

Clot busters are rarely used to treat DVT, but women with extensive blood clots in the veins of the abdomen or upper legs may benefit from clot busters as long as they have a very low risk of bleeding problems.⁹ Because blood clots that travel to the lungs are more likely to cause serious complications, clot busters are more often used to treat pulmonary embolism. You may benefit from clot busters if you have been diagnosed with pulmonary embolism and you:⁹

• Lose consciousness
• Are not getting enough oxygen because the clot is blocking blood flow to a large part of the lungs
• Have very low blood pressure ( hypotension)
• Develop heart failure
• Already have heart or lung disease

Who should not receive clot busters?

You should not receive clot busters if you are currently bleeding (such as because of a recent injury or surgery, stomach ulcer, or bleeding stroke) or if you have other conditions that make bleeding more likely. Certain other medications, such as warfarin and aspirin, can make bleeding problems worse when combined with clot busters.

If you are unable to take clot busters because the risk of bleeding is too high, the clot may need to be removed with surgery or other methods. See DVT Treatment Overview to learn more.

What are the risks of clot busters?

As with other drugs to treat DVT and PE, the main risk of clot busters is excess bleeding. Because of this risk, clot busters are only used in life-threatening situations. If you are being treated with clot busters, your doctor has determined that the benefits of restoring blood flow quickly outweigh any bleeding risks.

If you are having a procedure in which the clot buster is injected directly onto the clot through a catheter, there is a small risk of complications including:

• Infection of the incision where the catheter was inserted
• Damage to your arteries from the catheter
• An allergic reaction to the X-ray dye used in the test

References

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