Deep Vein Thrombosis (DVT): Symptoms, Causes, Treatment

Medically Reviewed by Poonam Sachdev on June 14, 2023
9 min read

If blood moves too slowly through your veins, it can cause a clump of blood cells called a clot. When a blood clot forms in a vein deep inside your body, it causes what doctors call deep vein thrombosis (DVT). This is most likely to happen in your lower leg, thigh, or pelvis. But it can occur in other parts of your body, too.

DVT can lead to major health problems. In some cases, it can be fatal. That’s why if you think you have one, you must see a doctor right away.

Not everyone with DVT shows symptoms. But you might notice any of the following:

  • Leg or arm swelling that comes on without warning
  • Pain or soreness when you stand or walk
  • Warmth in the area that hurts
  • Enlarged veins
  • Skin that looks red or blue

If a blood clot breaks free and moves through your bloodstream, it can get stuck in a blood vessel of your lung. Doctors call this a pulmonary embolism, or PE. It can be fatal.

Some people don’t know they have DVT until this happens. Signs of PE include:

Learn more about DVT symptoms

The causes of DVT include things that keep blood from:

  • Flowing through your leg, thigh, or pelvis
  • Clotting correctly

This usually happens as a result of damage to one of your veins due to:

  • Surgery
  • Inflammation
  • Infection
  • Injury

Many things can raise your chances of getting DVT. Here are some of the most common:

  • Age. DVT can happen at any age, but your risk is greater after age 40.
  • Sitting for long periods. When you sit for long stretches of time, the muscles in your lower legs stay still. This makes it hard for blood to circulate, or move around, the way it should. Long flights or car rides can put you at risk.
  • Bed rest. When you’re in the hospital for a long time, this can also keep your muscles still and raise your odds of DVT.
  • Pregnancy. Carrying a baby puts more pressure on the veins in your legs and pelvis. What’s more, a clot can happen up to 6 weeks after you give birth.
  • Obesity. People with obesity – that's a body mass index (BMI) of 30 or higher – are at a higher risk. BMI measures how healthy your weight is based on how tall you are.
  • Serious health issues. Conditions like inflammatory bowel disease, cancer, and heart disease can all raise your risk.
  • Certain inherited blood disorders. Some diseases that run in families can make your blood thicker than normal or cause it to clot more than it should.
  • Injury to a vein. This could result from a broken bone, surgery, or other trauma.
  • Smoking . This makes blood cells stickier than they should be. It also harms the lining of your blood vessels. This makes it easier for clots to form.
  • Birth control pills or hormone replacement therapy. The estrogen in these raises your blood’s ability to clot. (Progesterone-only pills don’t have the same risk.)
  • Infection. When in your blood, veins, or elsewhere, it could lead to DVT.
  • Inflammation. This could be due to infection, surgery, injury, or some other root cause.
  • High cholesterol.

In some cases, neither the cause nor the symptoms of DVT are very clear, so tell your doctor about any changes you notice if you are at higher risk for DVT.

How many people get DVT? 

DVT symptoms can be hard to find and often go unnoticed. So it's hard to estimate the number of diagnoses . But it's thought that about 8 in every 10,000 people get DVT every year. And lower-leg DVT happens  in every 1 in 1,000 people. But these numbers actually could be higher.

Your doctor will first do a physical exam of your leg and lower body areas to check for symptoms. If there is any swelling, tenderness, or change in skin color, they will likely want to run some tests to see if you have DVT. Such tests include:

  • Duplex ultrasound. This is the standard test for DVT. Your doctor will run an ultrasound to scan parts of your body for clots in your veins. An ultrasound scanner sends sound waves to create images showing how blood flows through your veins.  If your doctor finds a clot, they may want you to come back for more ultrasounds to see if it has grown or if there are any new ones.
  • D-dimer blood test. Most people with bad DVT will have D-dimer in their blood, It's a type of protein that comes from blood clots. Your doctor will do a blood test to see whether you have high levels of D-dimer.
  • MRI. MRIs are usually done for DVT in the lower abdomen or belly area. They are not standard for the more common forms of DVT.
  • Venography. This test is rarely done because it is so invasive. Your doctor will inject dye in your veins and take an X-ray to see if the dye is flowing properly through your veins. It can let your doctor to see if you have any clots. Other tests, like an ultrasound, are done first.

Find out more about DVT tests and diagnosis

DVT can progress as your symptoms get worse. Signs of acute DVT include: 

  • Pain in your leg or arm. It could be swollen and feel warmer than it normally does. 
  • You may notice a change in skin color. It might be red. If you have a darker skin tone, this may be harder to see. 
  • A bad headache that can come on suddenly. You might also have seizures.
  • Bad belly pain (if blood clots are in your abdomen)

If you are breathless or have chest pain, this can be a bad progression in your DVT. You might feel lightheaded or faint. If this happens, you need medical care right away. These could be signs of a pulmonary embolism (PE), when the clot is going into your lungs. PE can be fatal if it's not caught early enough.

 

Your doctor will want to stop the blood clot from getting bigger or breaking off and heading toward your lungs. They’ll also want to cut your chances of getting another DVT.

This can be done in one of three ways:

Medications for DVT

Blood thinners are the most common medications used to treat DVT. They cut your blood’s ability to clot. You may need to take them for 6 months. If your symptoms are severe or your clot is very large, your doctor may give you a strong medicine to dissolve it. These medications, called thrombolytics, have serious side effects like sudden bleeding. That’s why they’re not prescribed very often.

Procedure for DVT

Inferior vena cava (IVC) filter. If you can’t take a blood thinner or if one doesn’t help, your doctor may insert a small, cone-shaped filter inside your inferior vena cava. That’s the largest vein in your body. The filter can catch a large clot before it reaches your lungs.

Home remedies for DVT

Compression stockings. These special socks are very tight at the ankle and get looser as they reach your knee. This pressure prevents blood from pooling in your veins. You can buy some types at the drugstore. But your doctor might prescribe a stronger version that an expert can fit for you.

Know more about the latest DVT treatments

Research shows that Black people are more likely to have DVT than White people. But they're just as likely or less likely to have PE. 

Studies show that people with what's known as "metabolic syndrome" are at greater risk of having a DVT event. Metabolic syndrome is a condition linked to a group of other conditions, such as obesity, high blood sugar, high cholesterol, and high blood pressure.

Black people, and especially Black women, tend to have metabolic syndrome more often than people of other racial groups. This can increase their chances of having DVT.

Up to half of people with DVT will have long-term complications because of damage to the leg vein (post-thrombotic syndrome) where blood remains too long (chronic venous insufficiency). You may notice pain, swelling, and redness, which can lead to open sores if you don’t get early treatment. In time, this can make it harder to do daily activities and even walk.

The biggest worry for a blood clot is a DVT that breaks off and causes a pulmonary embolism (see above). If the clot isn’t too big and you get the right treatment fast enough, you may recover from this, though there may be some long-term lung damage.

About a third of people who have had a DVT or PE have a higher risk of another incident.

Living with DVT can be very manageable if you stick to a good routine, eat well, and budget enough for out-of-pocket costs. It's also important to stay aware of your mental well-being during and after a DVT.

DVT diet

While it is always good to stick to a well-balanced diet, healthy eating is especially important if you have DVT. Inflammation is known to make the risk of blood clots higher. Here are some tips for eating to lower inflammation:

  • Try to include plant-based foods like fruits, veggies, nuts, and whole grains.
  • Olive oil and canola oil are good subs for butter.
  • If you're going to flavor your food, try herbs and spices instead of salt.
  • Red meat is fine, but try to keep it to no more than two to three times a month.
  • It's good to eat fish at least twice a week.

DVT costs

Research shows that people with DVT lose, on average, 57 short-term disability days at work and 440 long-term disability days. The out-of-pocket cost per year is about $2,500, including medical and pharmacy expenses. It may be more or less, depending on your insurance or if you are uninsured.

Managing DVT

After a DVT, you can slowly get back to your normal activities. 

  • If you sit for a while, it's good to stand up and walk for a few minutes every hour. This is especially true for road trips or long flights.
  • If you're sitting for a long time (like at work), exercise your calf muscles.
  • Always wear compression socks as prescribed by your doctor. This will help with swelling.
  • Try not to do anything that could cause a serious injury.
  • Drink plenty of water.

DVT and mental health

The trauma of going through a blood clot can cause mental health issues for you. These may include:

  • Anxiety
  • Depression
  • Posttraumatic stress disorder (PTSD)

If you have or think you may be having any of these or other mental health conditions as a result of your DVT, reach out to a mental health professional for one-on-one or group therapy.

Since a DVT can take up to a year to break apart, your doctor will likely want to do more ultrasounds after the first one to see if it has spread or gotten worse. 

Always take your blood thinners as prescribed and wear compression socks until your doctor tells you it's OK to stop. You might need more blood tests to check that you have the right dosage of medications as your DVT gets better or worse.

Can DVT be cured?

Yes. With the proper treatment and attention, your blood clot can come apart over time.

Simple lifestyle changes may help lower your odds of getting one. Try these simple tips to keep your blood circulating the way it should:

  • Take care of yourself. Stop smoking, lose weight, and try to be active.
  • Get regular checkups. And if your doctor has prescribed a medicine to control a health problem, take it as directed.
  • Don’t sit for too long. If you’re traveling for 4 hours or more, take breaks to flex and stretch your lower leg muscles. If you’re on a flight, walk up and down the aisle every hour. On long car drives, pull over every 2 hours to stretch. Wear loose-fitting clothes, and drink plenty of water.
  • Plan surgery after-care. Talk to your doctor about what you can do to prevent DVT after surgery. They might suggest you wear compression stockings or take blood thinners. You’ll also want to get out of bed and start moving around.

 

Deep vein thrombosis can be managed  and go away if your doctor finds and treats it early enough. With a healthy diet, meds, compression socks, and enough exercise, you can live a full life during and after your DVT. Talk to your doctor right away if you think you might have DVT.