Thrombolytics, or clot-busting drugs, get rid of blood clots that keep oxygen from reaching your vital organs. Providers can give you thrombolytics at the hospital or in an ambulance when you’re having a heart attack or stroke. This keeps the clot from doing more damage and gives you a better chance at surviving and recovering.


What are thrombolytic drugs?

Thrombolytics (fibrinolytic drugs) are “clot-busting” drugs that break up and dissolve blood clots that get in the way of your blood flow. Thrombolytics are enzymes that kick off the process of breaking down proteins (fibrins) that form clots.

If you have a stroke, heart attack or pulmonary embolism, your healthcare provider will likely give you thrombolytics as soon as possible, probably within a half-hour of getting to the hospital. A paramedic may even give you thrombolytics before you get to the hospital.

You should have thrombolytics within three hours of your stroke to help prevent long-term problems. Thrombolytics are used less commonly in heart attacks. This is because the most effective treatment for a heart attack is often coronary artery catheterization and possible stent placement.

If you aren’t close to a major hospital with a coronary catheterization laboratory, your healthcare provider may give you thrombolytics as soon as possible to prevent damage to your heart. Your provider can give you thrombolytics through an IV in your arm or through a catheter they insert at the clot’s location. These methods quickly get the medicine where it needs to go. The quicker it starts working, the sooner it can bring back normal blood flow to your blocked blood vessel.

Thrombolytic therapy can save your life and prevent a lack of oxygen from causing damage to your heart, brain or other affected area.

The different types of thrombolytic drugs include:

  • Alteplase (t-PA): This is often the top choice for strokes, pulmonary embolisms and cardiovascular cases. It rarely causes allergic reactions.
  • Anistreplase: Because this targets all plasminogen, not just the ones attached to fibrin, it can work throughout your whole body.
  • Prourokinase: Researchers are testing this new drug. It has to convert to urokinase to work.
  • Reteplase: This works faster than other thrombolytics.
  • Streptokinase: This is the one used most across the globe, but not much in America. It’s cheaper than others but many people have allergic reactions to it. Like anistreplase, it can affect your entire body.
  • Tenecteplase: This works efficiently and is a frequent choice of many providers in North America and Europe. It also has a smaller bleeding risk.
  • Urokinase: Healthcare providers may choose this for peripheral vascular clots (in the legs) and for catheters with clots. Many providers outside the United States choose this because it’s cheaper than other thrombolytic drugs.


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What do thrombolytics treat?

Healthcare providers use thrombolytics when blood clots become a serious problem, such as:

Thrombolytics vs. anticoagulants

Thrombolytics are used for emergencies. You won’t find them in your pharmacy, but hospitals and ambulances have them on hand for emergency treatment of heart attacks and strokes. Anticoagulants (“blood thinners”) are medicines (such as warfarin) that your provider can order for you. You take anticoagulants to keep your body from making dangerous blood clots. If anticoagulants are successful at preventing blood clots, you won’t have a need for thrombolytics.

Risks / Benefits

What are the advantages of thrombolytics?

They work quickly to get your blood moving again, which limits the amount of damage from a lack of oxygen. Researchers have found that people who get thrombolytics for their strokes have better chances of a complete recovery than those who don’t get the drug in the short time frame after their stroke happens.


What are the risks or complications of thrombolytics?

Thrombolytics can make you bleed without warning. One-fourth of the people who get thrombolytics can have minor bleeding. More rarely, you could have a serious or life-threatening bleed. The most feared complication is bleeding in your brain, which could cause a stroke. You’re more at risk for bleeding if you:

  • Are an older adult.
  • Tend to bleed easily.
  • Had a stroke or surgery recently.
  • Take a blood thinner.
  • Don’t have your blood pressure under control.

It’s possible that a small piece of a broken clot could make its way further into your body. Your provider can use imaging like a CT scan or echocardiogram to check for any leftover clot pieces. Also, thrombolytics give some people allergic reactions or low blood pressure. Your provider will keep checking your blood pressure to make sure you don’t have complications.

Recovery and Outlook

What is the recovery time?

Your recovery time will vary depending on the type of medical problem you had. You could spend a week in the hospital after a heart attack or stroke. Then you may need rehabilitation to help you with areas of your body that the heart attack or stroke damaged.


When To Call the Doctor

When should I see my healthcare provider?

You or someone with you should call 911 if you think you might be having a heart attack, stroke or pulmonary embolism. All of these are emergencies and you should seek treatment as soon as possible to reduce permanent problems. Calling an ambulance gives you the best chance of surviving these emergencies because treatment can start before you get to the hospital.

You should also call your provider if you think you might have venous thromboembolism or deep vein thrombosis.

Additional Common Questions

Is heparin a thrombolytic drug?

No, heparin isn’t a thrombolytic drug. It’s an anticoagulant that helps your body make clots more slowly. Your provider may prescribe this to keep you from having a stroke. It is given through an IV so it is only prescribed in the hospital. There are other medications that can be taken by mouth that might be prescribed for use at home to prevent another blood clot.

Is aspirin a thrombolytic drug?

No, aspirin isn’t a thrombolytic drug. It’s an antiplatelet drug that helps keep platelets from attaching to each other and making a clot. Your provider may ask you to take this to prevent another stroke or heart attack.

A note from Cleveland Clinic

When you have a stroke or heart attack, your healthcare provider may give you thrombolytic therapy to clear out the blood clot that’s causing your problem. Thrombolytic drugs can be very effective for destroying dangerous clots, but they need to be given within a short time frame. Be sure that you and your family know the signs of a heart attack and stroke so that you can call 911 to get help right away.

Medically Reviewed

Last reviewed on 06/12/2022.

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