Fibrinogen is a clotting protein made by the liver. It also rises with inflammation.
- Normal range (adults)
- 200–400 mg/dL (2–4 g/L)
- Sample
- Blood
- Fasting
- Not usually needed
- Also called
- Serum Fibrinogen, Fibrinogen Level, Factor I, Plasma Fibrinogen
Fibrinogen normal range
| Group | mg/dLConventional units: US, South Asia | g/LSI units: UK, Europe, Australia, international |
|---|---|---|
| Adults | 200–400 | 2–4 |
Your report may use either unit system; labs in the Gulf often print both. Ranges also vary slightly between laboratories, so the range printed on your own report is the one to go by.
Why is the Fibrinogen test done?
It is checked for bleeding problems and sometimes as a marker of inflammation.
What does a high Fibrinogen level mean?
High fibrinogen is common with inflammation, pregnancy and smoking, and is linked to higher heart risk.
Common causes
- Infection and inflammation
- Pregnancy
- Smoking
- Overweight
Diet and lifestyle tips
- Stop smoking
- Anti-inflammatory diet and regular exercise
What does a low Fibrinogen level mean?
Low fibrinogen increases bleeding risk.
Common causes
- Severe liver disease
- Massive bleeding or DIC
- Inherited deficiency (rare)
Diet and lifestyle tips
- Medical treatment is needed
When should you see a doctor?
Low fibrinogen with bleeding is an emergency.
Last updated
This page is for general education and is not a diagnosis. Normal ranges differ between laboratories, so always compare your result with the reference range printed on your own report, and discuss abnormal results with your doctor.