Fibrinogen (serum/plasma) concentration

This test measures the amount of fibrinogen in your blood. Fibrinogen is a protein made by the liver that helps your blood clot properly. Your doctor may order this test if you have unexplained bleeding or bruising, if a blood clot has formed, to help check for conditions such as disseminated intravascular coagulation (DIC), or to see how well your liver is working. It is often done together with other clotting tests such as PT and aPTT.

Your doctor may order a fibrinogen test to check for bleeding disorders, clotting problems, or to monitor conditions like liver disease, where fibrinogen production can be affected. It may also be used before surgery to assess your risk of bleeding.

Usually, no special preparation is needed for this test. Tell your doctor about all medicines you take, including blood thinners such as warfarin or heparin, aspirin, and birth control pills, because some drugs can affect your fibrinogen level. A small blood sample will be drawn from a vein in your arm, most often on the inside of the elbow. You may feel a quick sting when the needle goes in, but the test is quick and generally very safe.

No special preparation is needed, but avoid aspirin or other blood-thinning medications for at least 48 hours before testing unless directed otherwise. Fasted or non-fasted blood draws are typically acceptable.

A health care professional will clean the skin on your arm, wrap an elastic band around your upper arm, and insert a small needle into a vein to collect blood into a tube. The sample is then sent to a laboratory, where a technician measures how much fibrinogen is present and how well it helps your blood form a stable clot. The blood draw usually takes only a few minutes, and a bandage is placed over the puncture site afterward.

Blood is drawn from a vein, usually in your arm. The sample is sent to a lab where fibrinogen levels are measured using a method that detects its ability to form clots.

A typical fibrinogen level falls between about 200 and 400 milligrams per deciliter (mg/dL), although exact reference ranges can vary from one laboratory to another. Results should always be interpreted along with your symptoms, medical history, and other clotting test results. Your doctor will explain what your specific value means for you and whether any additional testing or treatment is needed.

Results are reported as a mass concentration (e.g., grams per liter). Low levels may indicate bleeding disorders or liver disease, while very high levels could suggest conditions like multiple myeloma or severe inflammation.