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Home > Health Library > Deep Vein Thrombosis
Deep vein thrombosis (DVT) is a blood clot (thrombus) in a deep vein, usually in the legs. These clots require medical care right away.
These clots are dangerous because they can break loose, travel through the bloodstream to the lungs, and block blood flow in the lungs (pulmonary embolism). Pulmonary embolism is often life-threatening. DVT can also lead to long-lasting problems. It may damage the vein and cause the area near the clot to ache, swell, and change color.
Blood clots most often form in the calf and thigh veins, and less often in the arm veins or pelvic veins. Diagnosis and treatment of DVT in other parts of the body are similar.
Causes of a blood clot in a deep vein (DVT) include slowed blood flow, which can happen when you're not active for long periods of time, and abnormal clotting problems, which make the blood clot too easily or too quickly. Surgery or an injury to the blood vessels can also cause a blood clot.
Symptoms of DVT include swelling of the affected leg or arm. The leg or arm may swell, feel warm, or look red. The calf or thigh may ache or feel tender. Pain may get worse and last longer or become constant. If a blood clot is small, it may not cause symptoms.
If your doctor thinks that you have DVT, you probably will have an ultrasound test to measure the blood flow through your veins and help find any clots that might be blocking the flow. You will also have a physical exam, and the doctor will ask you questions about your past health.
Treatment for DVT usually involves taking blood thinners (anticoagulants) for at least 3 months. How long you take them depends on your health, where the blood clot is, and your risk for a pulmonary embolism. At home, you can take walks and you can prop up or elevate your leg or arm.
To help prevent DVT, you might take an anticoagulant medicine. After an illness or surgery, you can try to get up and out of bed often. You might wear compression stockings. You may try leg exercises that can help blood flow.
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Causes of a blood clot in a deep vein (DVT) include:
Many things increase your risk for DVT. These include:
DVT often doesn't cause symptoms. Or it may cause only minor ones. When symptoms happen, they include:
Sometimes a pulmonary embolism is the first sign that you have DVT.
If your doctor thinks you may have DVT, you will probably have an ultrasound test. You may have other tests as well.
A blood clot in a deep vein (DVT) may break loose. It if does, it can travel to the lungs and block blood flow (pulmonary embolism). This is an emergency.
The risk of a pulmonary embolism can depend on the location of the blood clot. A pulmonary embolism is more likely if a blood clot is at or above the knee than if it is in the calf. But a blood clot in a calf also has a chance of causing a pulmonary embolism.
After the first time you have DVT, there is a risk of having blood clots again. Your risk can depend on what caused the clot and how it was treated. Your doctor will treat you to try to prevent clots from happening again.
If you have had DVT, you have a risk of a painful complication called post-thrombotic syndrome. Anticoagulant medicine may help lower the risk of this complication.
Call 911 or other emergency services if you have pulmonary embolism symptoms, including:
Call your doctor now if you have DVT symptoms, including:
If your doctor thinks that you have DVT, you probably will have an ultrasound test to measure the blood flow through your veins and help find any clots that might be blocking the flow.
To see if you need an ultrasound, the doctor will do a physical exam. This will include checking your heart and lungs and checking your legs for warmth, swelling, bulging veins, or changes in skin color.
More tests may be used when ultrasound results are unclear. These can include a D-dimer test, MRI, or CT scan. These tests may help diagnose or exclude a blood clot.
If your doctor thinks you might have a pulmonary embolism, he or she may test your lungs.
The main goals of treatment for DVT are:
Treatment includes medicine and self-care.
DVT is usually treated with anticoagulant medicines. These medicines are often called blood thinners, but they don't actually thin the blood. They prevent blood clots by increasing the time it takes a blood clot to form. They also help prevent existing blood clots from becoming larger.
You might take anticoagulants for at least 3 months. The length of time will vary based on your own health and your risk for a pulmonary embolism.
Other treatments may be used in the hospital for some people. These treatments include thrombolytic medicine, a procedure to remove the blood clot (thrombectomy), and vena cava filters. But these treatments aren't common. They might be used for people who are at risk for serious problems from DVT.
Your doctor may also recommend self-care to relieve symptoms. This care includes:
Home treatment for DVT focuses on:
You can do a few things to treat your DVT at home.
If you take an anticoagulant medicine, also called a blood thinner, you need to take extra steps to avoid bleeding problems.
Walking can help relieve symptoms like pain and swelling.
This also helps with pain and swelling.
Compression stockings are specially fitted stockings. They are tightest at the foot. They get less and less tight farther up on your leg.
Your doctor might suggest that you take a nonsteroidal anti-inflammatory drug (NSAID), such as ibuprofen, to relieve pain. Do not take an NSAID unless your doctor tells you that it's safe for you.
Anticoagulant medicines, also called blood thinners, are used to prevent and treat DVT.
These medicines prevent new clots from forming. They also prevent existing clots from getting larger. They don't get rid of existing clots.
Different types of anticoagulants are used. Talk with your doctor about which medicine is right for you.
If you are in the hospital, you might be given an anticoagulant as a pill, a shot, or in a vein through an IV. After you go home, you might give yourself shots for a few days. For long-term treatment, you'll likely take a pill.
You might take anticoagulants for at least 3 months. You may take them for a much longer time, maybe even the rest of your life. The length of time will be based on your health and your risk for a pulmonary embolism.
Current as of:
July 6, 2021
Author: Healthwise StaffMedical Review: E. Gregory Thompson MD - Internal MedicineAdam Husney MD - Family MedicineKathleen Romito MD - Family MedicineJeffrey S. Ginsberg MD - Hematology
Current as of: July 6, 2021
Author: Healthwise Staff
Medical Review:E. Gregory Thompson MD - Internal Medicine & Adam Husney MD - Family Medicine & Kathleen Romito MD - Family Medicine & Jeffrey S. Ginsberg MD - Hematology
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