Fibrin is a protein involved in the clotting of blood. It is a fibrillar protein that is polymerised to form a "mesh" that forms a haemostatic plug or clot (in conjunction with platelets) over a wound site.

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... Why get tested?
To determine whether your fibrinogen level is adequate to allow normal blood clotting, to help diagnose disseminated intravascular coagulation (DIC), to help determine whether you have an inherited fibrinogen deficiency or abnormality. Sometimes to help evaluate your risk of developing cardiovascular disease.

When to get tested?
When you have unexplained or prolonged bleeding, an abnormal Prothrombin Time (PT) or activated Partial Thromboplastin Time (aPTT) test, or have a relative with a hereditary fibrinogen deficiency or abnormality.  When your doctor wants additional information to help evaluate your risk of developing heart disease.

Sample required?
A blood sample drawn from a vein in your arm, or sometimes, via fingerstick.
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