Fibrinogen · low result
What does a low Fibrinogen mean?
Short answer
Low fibrinogen means either the liver is making less (advanced liver disease, malnutrition) or it is being consumed faster than it can be made — disseminated intravascular coagulation in sepsis or severe illness, major bleeding, or after thrombolytic drugs. Rare inherited deficiencies exist. A low fibrinogen raises bleeding risk and, below about 100 mg/dL, is a finding to act on the same day.
Medically reviewed by Youmna DiStefano, MD · Last reviewed September 2026
When does this result need same-day care?
- Fibrinogen under ~100 mg/dL, or any low value with active bleeding — emergency care
What is the normal range for Fibrinogen?
- age 18+: 200 – 400 mg/dL
Can reflect liver disease, severe bleeding, or rare genetic factor deficiency.
Full reference table, citations and testing options: Fibrinogen biomarker page.
What are the common causes of low Fibrinogen?
- Advanced liver disease, cirrhosis
- Disseminated intravascular coagulation (sepsis, trauma, obstetric emergencies, some leukemias)
- Massive bleeding or transfusion, thrombolytic therapy
- Malnutrition, L-asparaginase chemotherapy
- Inherited afibrinogenemia or dysfibrinogenemia (rare)
What symptoms go with low Fibrinogen?
- Easy bruising, prolonged bleeding, nosebleeds
- Often none when mildly low
What do clinicians usually check next?
- PT/INR, aPTT, platelet count, D-dimer, liver panel
- Hematology review for persistent unexplained low values
Follow-up tests available at TestWell: PT and PTT (Prothrombin & Partial Thromboplastin Time) ($54.99), D-Dimer ($69.99).
How do you recheck Fibrinogen?
Prices are cash-pay; every order adds one $6 lab processing fee. Physician authorization is included; no insurance or referral needed.
| Test or panel | Type | Price | Fasting | Results |
|---|---|---|---|---|
| Blood Clotting Panel | Panel · 4 tests | $149.99 | No | 3–7 business days |
| Inflammation Panel | Panel · 7 tests | $119.99 | Yes | 2–5 business days |
| Total Body Panel | Panel · 49 tests | $499.99 | Yes | 5–10 business days |
| Fibrinogen Activity | Test | $22.99 | No | 2–4 business days |
Common questions
Can fibrinogen be low in a healthy person?
Mild lows occasionally appear in slim, very fit people and some inherited variants without symptoms. Anything under 150 mg/dL, or a drop from a previous result, should be repeated and explained.
Educational content, not a diagnosis. Lab results are one input; a clinician interprets them with your history and exam.