Leg with many veins and a large cluster in the middle

What Is Deep Vein Thrombosis (DVT)?

Deep vein thrombosis (DVT) is a blood clot that can form in a deep vein. It usually occurs in the legs but can occur in other parts of the body.1,2

DVT can be very serious. If a blood clot in a vein breaks loose, it can travel through the bloodstream and get stuck in the lungs. This can block blood flow. When this happens, it is called pulmonary embolism (PE).1,2

More than 200,000 people develop DVT in the United States every year. About one-quarter of those cases result in a PE. When DVT and PE happen together, it is called venous thromboembolism (VTE). VTEs are the third most common cause of death, after heart attack and stroke.1,2

What are the risk factors for DVT?

There are many risk factors for DVT, including:1,2

  • Having damage to a vein caused by surgery, injury, or infection
  • Being over 60 years old
  • Taking certain drugs, such as birth control pills or drugs that replace hormones
  • Being pregnant
  • Being a smoker
  • Having cancer
  • Being overweight
  • Having inflammatory bowel disease (IBD)
  • Having a genetic blood clotting disorder
  • Having had a previous DVT or a family history of DVT

Another major risk factor for DVT is inactivity. When you do not use your leg muscles, the blood flow in your legs decreases. This increases your risk of DVT. People who have surgery, are on bed rest, or travel on long flights are more likely to develop DVT.1,2

DVT can occur even if you have no risk factors. Knowing the symptoms of DVT is important to help you avoid related health problems (complications) such as PE.1

What are the symptoms of DVT?

DVT can occur with no symptoms at all. Only about half of people with DVT experience symptoms. Symptoms can include:1,2

  • Leg pain, cramping, or soreness
  • Leg swelling
  • Feeling of warmth in your leg
  • Redness or other changes to the skin color of the leg

How is DVT diagnosed?

Doctors diagnose DVT with the help of the following tests:1,2

  • D-Dimer – A blood test that measures a piece of a protein (D-Dimer) that your body makes when a blood clot dissolves
  • Coagulation blood tests – Blood tests that provide information about your body’s ability to clot
  • Ultrasound of your leg veins

If you have an ultrasound that does not show DVT, your doctor may order a repeat ultrasound in 1 to 2 weeks or repeat blood tests as needed.2

How is DVT treated?

Treatment for DVT includes drugs that can break down or prevent blood clots (anticoagulation drugs). Treatment with these drugs usually lasts 3 to 6 months. If the DVT occurs more than once, 12 months of treatment may be needed. People with cancer need long-term treatment.2

Many people recover from DVT with no complications. However, they have a high risk of developing another DVT.2

How can DVT be prevented?

Prevention is key for DVT. These lifestyle changes can help prevent DVT:1,2

  • Keep moving. This is especially important if you have had surgery or are on bed rest. Try to move as early and as often as you can. If you are traveling, take breaks, stand, and stretch your legs.
  • Exercise. Aim for at least 30 minutes of moderate physical activity every day.
  • Don’t smoke.
  • Maintain a healthy weight.

If you notice symptoms of DVT, call your doctor and get started with treatment right away.

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