Deep vein thrombosis (DVT) is the formation of a blood clot in a vein that runs between muscles deep inside your body. Your veins are the blood vessels that return blood to your heart. Though a DVT can occur anywhere in the body, it's most common in a vein in the pelvis, thigh or lower leg.

DVT is a serious problem because the clot can break loose and travel through your blood. It's then called an embolus. If it reaches your lungs, it is known as a pulmonary embolism (PE) and can cause life-threatening lung damage.

You can have a DVT but have no symptoms. If you do have symptoms, they may include:

• Warmth over the area of the DVT
• Swelling of the leg or thigh
• Redness of the skin over the DVT
• Pain or tenderness, especially when standing or walking

Let your doctor know right away if you have any of these symptoms.

Sometimes, a PE is the first sign of DVT. Symptoms of PE come on suddenly and can include chest pain and difficulty breathing. If you have these symptoms, call 911 or go to the emergency room.

DVT may be caused by an injury to the inside of a vein, slow blood flow through a vein or a condition that increases blood clotting. You're more likely to develop DVT if you've had this condition before or if you have a family history of DVT or PE. Other risk factors include:

• Inactivity, such as being bedridden or taking long trips
• Recent surgery or injury
• Taking hormone replacement therapy or birth control pills
• Pregnancy, or having recently given birth
• Having cancer or recent cancer treatment
• Being older than 60
• Excessive weight
• Having a tube inserted into a major vein for a medical treatment (central venous catheter)
• Smoking
• Being born with a disorder that increases blood clotting
• Other medical conditions like heart or lung disease, or inflammatory bowel disease such as ulcerative colitis or Crohn’s disease.

The first step in diagnosing DVT is a physical examination and a thorough review of your medical history. Your doctor will ask about your symptoms and any risk factors for DVT. During the physical exam, your doctor will look for signs of DVT.

Several tests may be done to confirm a DVT diagnosis. These include:

Ultrasound

• Produces images of blood flow and blood vessels using sound waves
• The technician places clear, water-based gel on the affected area. A handheld probe is then moved back and forth over the area. As blood flows through the veins, the flow is shown on the computer monitor.

D-dimer Blood Test

Looks for substances in your blood that are released when a blood clot forms and dissolves.

A sample of your blood will be drawn and then tested.

Venogram

• Produces images of any obstructions to the blood flow in your veins
• Liquid dye is injected into a vein leading to the suspected blood clot area. A series of images are then taken to view blood flow through the veins.

Other Tests

Blood tests may be done to look for abnormal blood clotting or a blood clotting disorder.

Imaging studies may be done of deep blood vessels and your lungs. These may include an MRI, a CT scan or a lung scan.

The goal of treatment for DVT is to keep the clot from getting bigger, keep it from becoming an embolus and prevent other clots from forming. Treatment may include:

Anticoagulants: Also called blood thinners, these are the most common medications used to treat DVT. They reduce your body’s ability to form blood clots. They will prevent a clot from getting larger and prevent more clots from forming. These medications are started as soon as DVT is diagnosed.

Heparin, which may be the first anticoagulant used, starts to work quickly. It's given as an injection under the skin or as a continuous infusion into a vein. Although heparin given as an injection under the skin is sometimes used alone for the entire course of treatment of a DVT, heparin is usually used for only a few days while another blood thinner, like warfarin, is taking effect.

Warfarin is usually started at the same time as heparin and then continued after heparin is stopped. It's an oral medication that takes several days to take effect. Heparin is discontinued once warfarin has adequately taken effect. You will likely take warfarin for a few months or more. You'll need periodic blood tests to make sure you're getting the right amount of this drug.

Direct thrombin inhibitors and factor Xa inhibitors are newer anticoagulants and are alternatives to heparin and warfarin. Most are taken orally. These drugs interfere with clotting and take effect quickly. Unlike warfarin, they're not given with heparin, and you won't need blood testing to check your levels. You will likely take these drugs for a few months or more.

Thrombolytics: These medications dissolve blood clots. They may be used in certain high-risk situations. They're injected directly into a vein near the clot.

Vena cava filter: This device is inserted in the large vein that carries blood to your heart. The filter prevents a clot from traveling to your lungs. You may need this if other treatments have not worked or you cannot take anticoagulants.

Leg elevation: Keeping your legs raised above your heart encourages blood flow back to your heart and cuts down on leg swelling.

Compression stockings: These help blood flow and diminish swelling.

Warm baths or heating pads: Both of these ease discomfort by relaxing your muscles. They also help encourage blood flow and clot shrinkage.

Once you've developed a blood clot deep in the veins in your legs—deep vein thrombosis, or DVT—the proper treatment is essential. A DVT is an emergency, so it's important to seek immediate medical attention for warning signs such as swelling, heat, redness or tenderness in one leg.

"DVT is considered an emergency requiring immediate medical therapy," says Thomas Naslund, MD, chief of the division of vascular surgery at Vanderbilt University Medical Center in Nashville, Tennessee. "That medical therapy would be anticoagulation."

What Is Anticoagulation Therapy?

Anticoagulation therapy uses medications, often called blood thinners, that keep blood from clotting, prevent clots from growing and stop new clots from developing. The most significant side effect of anticoagulant drugs is bleeding, which can happen quickly and be life-threatening.

You can get started on anticoagulation therapy as an outpatient treatment at an emergency department or doctor's office, Naslund says, but it's important that your doctor monitor you closely after the treatment. It may be given orally, by injection, or intravenously. Common anticoagulants used to treat DVT are heparin, Coumadin or Jantoven (warfarin), and blood thinners similar to heparin including enoxaparin (Lovenox), dalteparin (Fragmin) or fondaparinux (Arixtra).

Anticoagulation is needed to prevent pulmonary embolism, a complication of DVT in which a clot breaks loose from the leg and travels to the lungs, Naslund explains. But if you can't tolerate anticoagulation therapy, doctors may use a filter in the major vein inside the abdomen, called the inferior vena cava, to trap blood clots traveling from the legs and stop them before they reach the lungs, he says.

As part of anticoagulation treatment, you'll need to stop taking medications that can interfere with your anticoagulants, such as hormone therapy, which may increase the risk of blood clots.

Anticoagulation therapy usually lasts from three to six months in people who've had a DVT, Naslund says.

Since 2012, three oral anticoagulants have been approved by the FDA to treat DVT and help reduce the risk of future blood clots from forming. They include apixaban (Eliquis), rivaroxaban (Xarelto) and edoxaban (Savaysa).

Thrombin inhibitors, such as dabigatran (Pradaxa), are medications that also help stop blood from clotting, generally in people who are unable to safely take heparin. They can also help people who can’t take heparin.

Other DVT Treatments

For large and life-threatening blood clots, you'll need a more serious treatment. Thrombolytic medications—tissue plasminogen activators, or tPAs—dissolve large, dangerous blood clots. So why aren't they used on all clots? They're risky: They can cause dangerous and rapid bleeding.

Preventing Another DVT

After the immediate treatment, you'll need to take steps to prevent more blood clots.

You may need to wear compression stockings. These are snug-fitting stockings that squeeze your legs so that blood doesn't pool there and allow clots to form.

Sitting for long periods of time, like on long flights, increases the risk for DVT, Naslund says. Drinking alcohol or becoming dehydrated while sitting can also contribute. If you must travel, try to get up and walk around frequently and drink plenty of water.

And if you're ill or recovering from surgery, move around as often as possible to reduce your DVT risk.

Find a specialist for deep vein thrombosis treatment near you using Vitals.com.

As your DVT is diagnosed and treated, you may see several types of doctors. The following providers may make up your care team for this condition:

Surgeon: If you've had a recent surgery, your surgeon may be the first doctor to diagnose and treat your DVT.

Emergency room physician: If you come to the hospital because of symptoms of DVT, the first doctor to start treatment may be an ER doctor.

Primary care provider: If you go to your primary care doctor with symptoms of DVT, this doctor may start treatment for you. Your primary care doctor might be a family physician, general practitioner or internist.

Hematologist: If you need specialty care for DVT, you may see a hematologist. This doctor deals with the prevention, diagnosis, treatment and management of blood conditions and disorders, including DVT and other blood clotting disorders.

Interventional radiologist: This doctor is a radiologist with special training to do medical procedures. You may need this doctor if you have a vena cava filter placed into a vein to prevent an embolus from traveling to your lungs.

Now that you have an appointment with a health care provider about your deep vein thrombosis (DVT), what can you do to get the most out of it? Start by compiling a list of:

• Any family history of DVT or PE
• Your past medical history, including dates of any serious illnesses or surgeries
• Any allergies you have
• Any tests results from the past year
• Any symptoms you’re experiencing, along with when they started and what makes them better or worse

Questions to Ask Your Doctor About Deep Vein Thrombosis

After being diagnosed with DVT, you will probably have questions about your condition and care. Review this list of common concerns before your appointment, or print it to take with you.

Questions About My Diagnosis

• Can this diagnosis be confused with other conditions?
• What causes blood clots? Is there a difference between clots in the arteries and veins?
• What tests would confirm this diagnosis?
• Am I at a higher risk for reoccurrence?
• Am I in danger of developing clots in other areas of my body?
• Can this condition be fatal?
• Does this reflect a heart condition?
• Can I prevent blood clots from reoccurring?

Questions About My Treatment

• Is there medication that can cure my condition?
• What can I take or do to make my symptoms go away?
• Is there physical activity or exercise that would improve this condition?
• Will wrapping my leg improve the problem?
• How long will it be before my symptoms go away?
• Will I need frequent blood tests while taking this medicine?

Questions About My Lifestyle and Family

• Does DVT run in families?
• Will I need to keep my leg elevated?
• Will I be able to drive?
• Will I be able to work?
• Are there activities that I should avoid?
• Will I have to avoid long car rides or plane rides?
• Will I have to avoid any foods while taking this medicine?

Getting a diagnosis of deep vein thrombosis (DVT) is just the beginning of managing your condition. Though the clot that formed deep in your leg can be treated, it's still something you'll need to think about long after your clot is cleared.

Here's what you need to know:

1. DVT is a medical emergency. Your doctors took immediate action at the time of your DVT diagnosis—to save your life. The most serious complication is a potentially life-threatening pulmonary embolism, when a blood clot in a deep vein travels to your lungs.

2. You're at risk for another DVT. Having one DVT increases the chances that you'll develop another. Your risk is 50 times higher than someone who hasn't had a DVT, according to research published in August 2015 in the journal Vascular Health and Risk Management.

3. Your treatment doesn't end when you leave the hospital. There are several ways to treat your DVT, but it's likely that you'll need to continue anticoagulation therapy to thin your blood and prevent another DVT. The usual minimum is about three to six months.

4. Your treatment has side effects. Anticoagulation therapy increases your risk for potentially serious bleeding, including internal bleeding. You'll need to be extra careful to prevent cuts and other injuries while you're taking blood thinners.

5. You may need follow-up blood tests. Your doctor may test your blood occasionally during your treatment. You want just enough medication to prevent a clot without making your blood too thin. If you are on certain medication, lab tests can tell your doctor that your dosage is correct by measuring how quickly your blood clots. If you bleed or bruise very easily, tell your doctor.

6. Tell your doctor what else you’re taking. Always check with your doctor about over-the-counter medications to manage pain, stomach discomfort, or the common cold, as well as herbs and supplements. These meds could interact with your blood-thinners.

7. Talk to your doctor about your health. Be sure to tell your doctor if you're pregnant or could be pregnant, and about any other health conditions that you have. These things may affect the way you and your doctor manage your DVT.

8. Watch what you eat and drink. Vitamin K is found in many leafy greens. It can interfere with warfarin, a type of blood thinner. It's also important to avoid alcohol while you're taking anticoagulants, as alcohol also thins the blood.

9. Use caution when traveling. Sitting still for a long period, such as a long car ride or plane ride, increases your risk for DVT. Alert your doctor to your travel plans. Take frequent breaks to walk around, and stretch your legs to keep the blood moving.

10. Work on the risk factors you can control. There are a few DVT risk factors—such as obesity and smoking—that you have the power to change. Follow a healthy diet, exercise regularly, and lose extra pounds. If you're a smoker, look into a quitting program.

Find a specialist focused on deep vein thrombosis treatment via Vitals.com

Once you've had a DVT, your risk goes up for having another. However, there are things you can do to help prevent a future DVT.

Make sure all your doctors know you've had a DVT. This is especially important if you have a major injury or are going to have any surgical procedure.

Avoid long periods of inactivity. After surgery or an illness, get out of bed and start walking as soon as possible.

When taking a long trip by car, train or plane, take breaks from sitting and do some walking. While you're sitting, flex your leg muscles and move your feet. Also, drink plenty of fluids (but avoid alcohol) and wear loose, comfortable clothing.

Ask your doctor if you should wear compression stockings to reduce leg swelling and improve blood flow.

Take all your medications and keep all your follow-up appointments.

If you have any symptoms of DVT, see your doctor right away.

Sources

National Heart, Lung, and Blood Institute, What Is Deep Vein Thrombosis? https://www.nhlbi.nih.gov/health/health-topics/topics/dvt

American Academy of Orthopaedic Surgeons, Deep Vein Thrombosis, https://orthoinfo.aaos.org/topic.cfm?topic=a00219

CDC, Venous Thromboembolism (Blood Clots), https://www.cdc.gov/ncbddd/dvt/facts.html

American College of Radiology, Inferior Vena Cava Filter Placement and Removal, https://www.radiologyinfo.org/en/info.cfm?pg=venacavafilter

Seminars in Interventional Radiology, Management of Chronic Deep Vein Thrombosis in Women, https://www.thieme-connect.com/products/ejournals/abstract/10.1055/s-0038-1636514

Mayo Clinic, Deep vein thrombosis (DVT), https://www.mayoclinic.org/diseases-conditions/deep-vein-thrombosis/symptoms-causes/syc-20352557

Medscape, edoxaban (Rx), https://reference.medscape.com/drug/savaysa-edoxaban-999979

National Heart, Lung, and Blood Institute, Venous Thromboembolism, https://www.nhlbi.nih.gov/health-topics/venous-thromboembolism

CDC, Diagnosis and Treatment of Venous Thromboembolism, https://www.cdc.gov/ncbddd/dvt/diagnosis-treatment.html