Coughing up Blood
This is a sign of a severe injury to the lungs or throat. Coughing up blood may also be a sign of a heart attack. In some cases, coughing up blood can be caused by a pulmonary embolism, which occurs when an artery in the lung becomes blocked by a clot. Pulmonary embolisms are rare but potentially life-threatening because they deprive the heart of oxygenated blood and can quickly lead to death if left untreated.
It is possible to cough up blood if a person has bronchitis or pneumonia. This happens because the lungs become inflamed and irritated, which causes them to produce more mucus than usual. It also makes it easier for small amounts of blood to seep into the mucus and be coughed up.
