. Fibrinogen is a protein in the body called a clotting factor. Clotting factors combine to form a blood clot, which helps stop bleeding when the body's tissues or blood vessels are damaged.
. Fibrinogen testing is used to evaluate and monitor symptoms such as difficult-to-stop bleeding or abnormal blockages (clots) in blood vessels. It detects increased or decreased levels of fibrinogen (factor I) that may be acquired or congenital and monitors the severity of treatment for disseminated intravascular coagulation and fibrinolysis.