What is a blood clot?

Blood clots are gel-like collections of blood that form in your veins or arteries when blood changes from liquid to partially solid. When you hurt yourself, clotting can stop your body from bleeding too much. It is a body function that can help in certain situations. But blood clots that form in some places can be dangerous.

A blood clot may stay in one spot (called thrombosis) or move through the body (called embolism). The symptoms of a blood clot, and the recommended treatment, depend on where a clot forms in your body and how much damage it could cause. Knowing the most common blood clot signs and risk factors can help you spot or even prevent this potentially life-threatening condition.

Which blood clots pose the most health risk?

Blood clots that form in arteries or veins can be serious. It is important to seek healthcare immediately if you suspect a blood clot.

A clot that forms in one of your body’s larger veins is called a deep vein thrombosis (DVT). A stationary blood clot, or one that stays in place, may not hurt you. A blood clot that dislodges and begins moving through the bloodstream can be harmful.

One of the most pressing blood clot concerns is when a DVT makes its way to your lungs and gets stuck. This condition, called pulmonary embolism, can stop blood from flowing and the results can be very serious, even fatal.

Who is most at risk for blood clots?

Several factors contribute developing a blood clot. Some definite risk factors put certain people at higher risk for developing a blood clot.

Blood clots become more common as people get older, especially over age 65. Long hospital stays and trauma may significantly increase your risk of blood clots.

Other factors can increase your risk to a lesser degree. You might be more at risk if you:

  • Take birth control pills or hormone supplements.
  • Are overweight or obese.
  • Are pregnant.
  • Live a sedentary (or inactive) lifestyle.
  • Smoke cigarettes.
  • Have cancer, or have been treated for cancer.
  • Have a family history of blood clots.
  • Have had recent surgery or prolonged immobilization.

What are the most common symptoms of a blood clot?

Blood clot symptoms will depend on where a clot forms in your body. Some people may experience no symptoms at all. Blood clots can occur in the:

  • Abdomen: Blood clots in the belly area can cause pain or nausea and vomiting.
  • Arms or legs: A blood clot in the leg or arm may feel painful or tender to the touch. Swelling, redness, and warmth are other common signs of blood clots.
  • Brain: Blood clots in the brain (strokes) can cause a range of symptoms, depending which part of the brain they affect. These clots may cause problems speaking or seeing. Sometimes, they cause seizures.
  • Heart or lungs: A blood clot in the heart will cause symptoms of a heart attack such as crushing chest pain, sweating, pain traveling down the left arm, and/or shortness of breath. A blood clot in the lungs can cause chest pain, difficulty breathing, and sometimes can lead to coughing up blood.

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