There are several causes of blood clots, with the main causes being a physical response to trauma, the effects of a medical condition or a reaction to medication. Though blood clotting is a normal function of the human body, blood clots can be problematic and life-threatening when they form and block blood and oxygen from traveling to blood vessels and arteries. Additionally, blood clots can cause a number of other health conditions if they are untreated.
In normal situations, causes of blood clots are non-threatening, and they form in response to injury in the body, such as a cut or break in the skin. The clots form when the cells in the lining of the blood vessels form platelets that act as a plug in the wall of the vessels. As the platelets clot together, fibrin, a type of protein that acts like glue, forms and causes the clot to hold together. When blood clots form normally through this process, it serves as a mechanism to prevent further infection or trauma to the site of injury. After the blood clot is no longer necessary, the body will naturally break it down.
In other cases, however, blood clots can threaten a person’s health. For instance, a blood clot can form and remain in the body’s blood vessels and arteries, which is called a thrombus. When the thrombus breaks away and travels to another part of the body, it is called an embolus. Some common causes of blood clots like these are a pulmonary embolism, a blood clot that has traveled to the lungs; and deep vein thrombosis, a blood clot that forms in the deep veins of the muscles in the legs. When blood clots such as these occur, they can partially or completely block blood flow and oxygen to other vessels and arteries, causing lasting damage to tissues in the body.
There are many other causes of blood clots. For example, genetic diseases can cause the development of clots. Thrombotic thrombocytopenic purpura (TTP) is one such condition that, though rare, creates many blood clots in the blood vessels of the organs. Additionally, some medications can cause the development of blood clots, such as medicines taken for oral contraception. Furthermore, poor health habits, such as smoking, obesity and a lack of exercise, can all contribute to the formation of blood clots.
The symptoms of the blood clots vary because the causes can be so different, and many people might not suspect that they are at risk for developing blood clots. Regardless, warnings can appear, such as pain, swelling and inflammation at the site where the clot has formed. Still, in many situations, blood clots are discovered only after a person has suffered a serious condition that is caused by the clot, such as a heart attack or stroke. In any case, treatment, surgery or medication is typically administered based on the specific condition of the clot to prevent further damage.