The risk of a blood clot traveling around the body is highest within the first 4 weeks after it initially forms. However, health experts are unsure of exactly how long it takes for a blood clot to travel around the body.

The above timeframe comes from an older 2014 article from the American Heart Association’s journal, Circulation.

A blood clot happens when various substances form a solid mass inside the blood vessels. These clots can form in one part of the body before breaking off from an artery or vein. The circulatory system can then carry this blood clot to blood vessels in different parts of the body.

In some cases, this can cause serious health problems. For instance, blood clots that originate in veins can travel to the lungs, leading to pulmonary embolism (PE). Blood clots that originate in the arteries can travel to the brain, causing a stroke.

This article explores how long it takes for a blood clot to travel. It also discusses possible signs that a blood clot is traveling and describes the treatment, outlook, and prevention for blood clots and their complications.

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Before a blood clot can travel, it must first break loose from the blood vessel it developed in.

An older paper in Circulation states that, on average, the risk of a blood clot breaking off is highest within the first 4 weeks of formation. This is because the blood clot is at its most fragile during this time.

It is difficult to know how long blood clots take to travel around the body. This is because blood clots can remain asymptomatic for some time. Some blood clots only cause symptoms after traveling to a different body part, such as the lungs or brain.

According to a 2022 review, scientists consider a blood clot to be acute if it starts causing symptoms 2 weeks after forming.

A person will not feel a blood clot traveling around their circulatory system. However, they may experience the following symptoms if the clot reaches the lungs or brain.

PE symptoms

The most common symptoms of PE include:

Stroke symptoms

The symptoms of stroke include:

Learn more about how a stroke feels.

According to a 2016 review, factors that increase the risk of a blood clot traveling through the body include:

If a person notices the signs and symptoms of a blood clot, they should contact a doctor. Treating a blood clot can help prevent the blood clot from causing complications.

A doctor will typically prescribe anticoagulant medications within 5–10 days of a diagnosis. Other treatments will depend on where the blood clot is. Options include:

  • wearing compression stockings
  • thrombolytic therapy (drugs that dissolve blood clots)
  • surgery to remove the clot
  • vena cava filter, which involves inserting a filter into the large vein in the abdomen

The treatment for a blood clot that has traveled depends upon where the blood clot has traveled to. For instance, if a blood clot travels to the lungs, it could cause PE.

According to the Centers for Disease Control and Prevention (CDC), the mainstay of PE treatment is thrombolytic therapy. These medications can dissolve blood clots. Doctors may also prescribe anticoagulants, which can stop further blood clots from forming.

If a blood clot travels to the brain, it could cause an ischemic stroke. According to the National Institutes of Health, doctors also prescribe thrombolytics and anticoagulants to treat ischemic strokes. They might also prescribe antiplatelet medications, which can help prevent blood clot formation.

Because strokes can cause brain damage, people who have had a stroke may require long-term rehabilitation.

The outlook for people whose blood clot travels depends on where the blood clot ends up.

According to a 2022 review, untreated PE is fatal in around 30% of cases. With prompt treatment, that figure drops to 8%. For ischemic stroke, a 2018 study estimates that around 11.1% of people die within 30 days of the stroke.

A person should contact a doctor if they notice any signs or symptoms of a blood clot. These include:

  • swelling that typically develops in one arm or leg
  • pain or tenderness around the clot
  • skin discoloration
  • skin that is warm to the touch

It is important that a person seeks emergency medical attention if they experience any signs and symptoms of PE or stroke.

Scientists do not know exactly how long it takes for blood clots to move around the body. However, they do know that blood clots tend to come loose within 4 weeks of forming. During this time, the clots are still fragile.

Doctors treat PE and ischemic strokes with medications that dissolve blood clots. They may also recommend medications that help prevent future clots from forming.