Deep vein thrombosis (DVT) is a condition that occurs when a blood clot forms in a vein deep inside a part of the body. It mainly affects the large veins in the lower leg and thigh, but can occur in other deep veins, such as in the arms and pelvis.
DVT; Blood clot in the legs; Thromboembolism; Post-phlebitic syndrome; Post-thrombotic syndrome; Venous - DVT
DVT is most common in adults over age 60. But it can occur at any age. When a clot breaks off and moves through the bloodstream, it is called an embolism. An embolism can get stuck in the blood vessels in the brain, lungs, heart, or another area, leading to severe damage.
Blood clots may form when something slows or changes the flow of blood in the veins. Risk factors include:
Blood is more likely to clot in someone who has certain problems or disorders, such as:
Sitting for long periods when traveling can increase the risk for DVT. This is most likely when you also have one or more of the risk factors listed above.
DVT mainly affects the large veins in the lower leg and thigh, most often on one side of the body. The clot can block blood flow and cause:
Your health care provider will perform a physical exam. The exam may show a red, swollen, or tender leg.
The two tests that are often done first to diagnose a DVT are:
A pelvic MRI may be done if the blood clot is in the pelvis, such as after pregnancy.
Blood tests may be done to check if you have an increased chance of blood clotting, including:
Your provider will give you medicine to thin your blood (called an anticoagulant). This will keep more clots from forming or old ones from getting bigger.
Heparin is often the first medicine you will receive.
One type of blood-thinning medicine called warfarin (Coumadin or Jantoven) may be started along with heparin. Warfarin is taken by mouth. It takes several days to fully work.
Another class of blood thinners works differently than warfarin. Examples of this class of medicines, called direct oral anticoagulants (DOAC), include:
These drugs work in a similar way to heparin and can be used right away in place of heparin. Your provider will decide which medicine is right for you.
You will most likely take a blood thinner for at least 3 months. Some people take it longer, or even for the rest of their lives, depending on their risk for another clot.
When you are taking a blood thinning medicine, you are more likely to bleed, even from activities you have always done. If you are taking a blood thinner at home:
In rare cases, you may need surgery instead of or in addition to anticoagulants. Surgery may involve:
Follow any other instructions you are given to treat your DVT.
DVT often goes away without a problem, but the condition can return. The symptoms can appear right away or you may not develop them for 1 or more years afterward. Wearing compression stockings during and after the DVT may help prevent this problem.
Complications of DVT may include:
Contact your provider if you have symptoms of DVT.
Go to the emergency room or call the local emergency number (such as 911) if you have DVT and you develop:
To prevent DVT:
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Reviewed By: Todd Gersten, MD, Hematology/Oncology, Florida Cancer Specialists & Research Institute, Wellington, FL. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.