What Are the Warning Signs of a Blood Clot?

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Blog What Are The Warning Signs Blood Clot

Blood clots are healthy and lifesaving when they stop external bleeding, but they can be dangerous or even fatal when they occur inside the body.

Internal blood clots form when blood doesn’t flow properly through the circulatory system. When this happens in the legs, it is known as deep vein thrombosis (DVT). Not everyone with DVT will have symptoms, so it’s important to exercise regularly, quit smoking, maintain healthy blood pressure levels, and talk to your doctor at the first sign of trouble.

These jelly-like masses of blood in the veins are extremely dangerous because DVT can break away from the vein wall and travel to other parts of the body. When it travels to the lungs, it is called pulmonary embolism (PE), a potentially life-threatening medical condition. Most pulmonary embolism blood clots start in the legs and travel up through the right side of the heart and into the lungs.

Blood clot warning signs include:

  • Sudden swelling in the affected leg
  • Pain, tenderness, or cramping in the leg when standing or walking
  • Skin discoloration (usually redness)
  • A feeling of warmth in the affected leg
  • Enlarged veins near the surface of the skin

Causes of deep vein thrombosis

A blood clot, or thrombus, can form for several reasons, including one or more of the following circumstances:


Trauma is one of the most common causes of DVT in the lower extremities.


When you sit more and move less, the blood flow to your legs slows down. This can cause the blood to pool in the muscular beds of the calf, making it easier for a clot to form. This can happen on an airplane flight or a long car ride.


An imbalance of the proteins and cells responsible for blood clotting can cause a person’s blood thicker or stickier than usual.


During pregnancy, a woman’s blood naturally clots more easily to lower her risk of extreme blood loss during labor and delivery.


Blood clots can form when blood slows down or the inside of the vein is injured, each common during and after surgery. Longer surgeries, particularly those using general anesthesia, pose a higher risk because of prolonged inactivity during the surgery and recovery.

Family history

If an immediate family member has a blood clotting disorder, you have an increased risk of DVT.


Being overweight increases your risk of stasis or stagnation of the blood in the veins, which also increases your risk of clot formation.


The risk of DVT increases after age 40.

Treatment options for DVT

The main goal for treating DVT is prevention. The first part of that goal is to prevent the clot from getting bigger. The second part prevents the clot from breaking loose and traveling to the lungs. The third is to reduce your chances of developing another clot. Safe and effective treatment options include:

Compression stockings: Medical-grade compression stockings lower your risk of blood clots and pooling in the lower extremities. They also help prevent swelling associated with DVT.

Anticoagulants: Blood-thinning medications are commonly used to prevent blood clots from getting bigger and reduce your risk of developing more clots. Most anticoagulants are prescribed for at least three months.

Thrombolytics: Clot-busting medications are prescribed for more serious cases of DVT or if other medications aren’t working. These medications can cause serious bleeding, so they are typically reserved for in-hospital administration for people with severe blood clots.

Filters: Filters are an alternative surgical option for those who cannot take blood-thinning medications due to drug interactions. During the procedure, your vein care specialist will insert a filter into a large vein in your abdomen called the vena cava. This is usually performed through one of the veins in the leg. This will help prevent clots that break loose from entering the lungs.

What to do if you suspect DVT

If you experience any sign of deep vein thrombosis, ask your healthcare provider to refer you to a Center for Vein Restoration location near you for expert care and treatment. Our specialists are skilled and experienced in the safe treatment of several vein problems, like spider veins, varicose veins, venous insufficiency, and deep vein thrombosis.

About Lawrence Jay Markovitz, MD, FACS

A highly skilled thoracic surgeon, Dr. Markovitz is certified by the board and has extensive experience in performing surgeries related to the heart and chest. In 2008, he shifted his professional attention toward diagnosing and treating venous disorders.

With his background as the former president of Virginia Vein Care in McLean, Virginia, Dr. Markovitz has joined Center for Vein Restoration. He is the lead physician at vein clinic locations in McLean, Virginia, and Purcellville, Virginia.

Are you experiencing any warning signs of blood clot? Schedule an appointment with Dr. Markovitz today!

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