Symptoms

Deep vein thrombosis often does not cause symptoms or causes only minor symptoms. When symptoms occur, they include:

• Swelling.
• Warmth.
• Pain or tenderness. The pain may be in the calf or thigh and may be present only when the affected area is touched or when standing or walking.
• Redness.

Other problems may cause symptoms like those of DVT. So diagnosing DVT can be difficult. These problems include less serious problems like cellulitis or a pulled muscle.

Symptoms of pulmonary embolism

Sometimes life-threatening pulmonary embolism is the first sign that you have DVT. Pulmonary embolism is the sudden blockage of an artery in the lung. Symptoms of pulmonary embolism include:

• Sudden shortness of breath.
• Chest pain that may get worse with a deep breath.
• A cough that may bring up blood.
• A fast heart rate.
• Fainting.

What Happens

Pulmonary embolism

When you have deep vein thrombosis (DVT), the main goal of treatment is to prevent the blood clot from growing or moving to the lungs. If a blood clot breaks loose, it can travel to the lungs and block blood flow (pulmonary embolism). A pulmonary embolism is an emergency. Treatment for DVT lowers your risk for this problem.

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.

For more information, see the topic Pulmonary Embolism.

Risk of more blood clots

After the first time you have deep vein thrombosis, there is a risk of having blood clots again. Your risk can depend on what caused your blood clot and how it was treated. Your doctor will treat you to try to prevent blood clots from happening again.

Postthrombotic syndrome

If you have had DVT, you have a risk of a painful complication called postthrombotic syndrome. You can help lower the risk of this complication with medicine and compression stockings.