Skip to content

Serum or plasma concentration of total bilirubin

Published: August 9, 2026Updated: August 16, 2026

This test measures the total amount of bilirubin in your blood, a byproduct of red blood cell breakdown that your liver helps process.

Quick summary

["Bilirubin helps your doctor check liver function and detect conditions like jaundice or bile duct issues."]

Medically reviewed by WellAlly Editorial TeamLast reviewed August 16, 2026Editorial policy

Key facts at a glance

LOINC
19259-1
Short code
N men sg A+C+W135+Y Ag Spec Ql LA
Synonyms
N men sg A+C+W135+Y Ag Spec Ql LA
Category
chemistry
Sample
serum
Container
Red-top tube (SST)
Units
N/A
Fasting
false
Population
adult
Sex
all
Age range
18–65 years
Method
la
Specimen volume
5 mL
Stability
Room temperature: 4h, Refrigerated: 24h, Frozen: 7d
Hemolysis max
500
Lipemia max
1000
Icterus max
500
TAT
4–24 hours
Order
routine

Why Is This Test Done?

Your healthcare provider may order this test to diagnose or monitor conditions affecting your liver, bile ducts, or red blood cells. It can also help identify signs of hemolysis (red blood cell destruction) or liver diseases like hepatitis or cirrhosis.

What to Expect Before the Test

No special preparation is needed. You may drink water beforehand, but avoid eating or drinking anything for 8–12 hours before the blood draw if instructed. Wear comfortable clothing and plan for the test to be done at a lab or clinic.

How the Test Works

A healthcare professional will draw blood from a vein in your arm. The sample is sent to a lab where bilirubin levels are measured using a colorimetric method to detect its presence in serum or plasma.

What the Results Mean

High bilirubin levels may indicate liver problems, blocked bile ducts, or red blood cell disorders. Low levels are less common but could suggest certain liver or metabolic conditions. Your results will be compared to standard reference ranges provided by your doctor.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

Clinical Significance: Elevated bilirubin is often associated with jaundice (yellowing of skin/eyes), liver inflammation, or blockages in the bile flow. It can also signal underlying conditions like hemolytic anemia or genetic disorders affecting bilirubin metabolism.

Short name

Total bilirubin

Frequently asked questions

What causes elevated bilirubin?
Elevated bilirubin can result from liver disease, bile duct obstructions, or increased red blood cell breakdown. Conditions like hepatitis, cirrhosis, or gallstones may contribute.
What if my bilirubin is low?
Low bilirubin is less common and may occur with certain liver diseases, metabolic disorders, or rare genetic conditions. Your doctor will discuss findings in the context of your overall health.
How often should I get this test?
Frequency depends on your health status. Your doctor may recommend this test periodically if you have liver-related conditions, during pregnancy, or as part of routine checkups for certain risk factors.
  1. 1
    MedlinePlus — Laboratory TestsSource
  2. 2
    Lab Tests OnlineSource
  3. 3
    Mayo Clinic — Tests & ProceduresSource

Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.

This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.

Medical Disclaimer

This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.

If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.

Medically reviewed by WellAlly Editorial Team Last reviewed August 16, 2026. · Read our editorial policy