Can this result diagnose a condition on its own?

No. Laboratory results are interpreted with symptoms, medical history, specimen conditions and related tests.

Which reference range should I use?

Start with the performing laboratory's own reference interval; clinical cutoffs, when relevant, are separate sourced thresholds used for a specific purpose.

When should I discuss the result with a healthcare professional?

Results that are clearly outside range, persistent, symptomatic or unexpected should be reviewed by a healthcare professional.

Information about a laboratory test

High Total Bilirubin: What Does It Mean?

High total bilirubin may occur with increased red-cell breakdown, altered bilirubin processing, liver disease or bile-duct obstruction, among other contexts.

Test summary

Test name: Total Bilirubin
Abbreviations: TBIL, TSB
Category: Hepatology / Bilirubin Metabolism
Panel: Liver Function Panel
Specimen: Serum / plasma
Common units: mg/dL, µmol/L

What does the test measure?

Measures the total amount of bilirubin in blood, including conjugated (direct) and unconjugated (indirect) bilirubin.

Why is the test ordered?

Used to investigate jaundice and to help assess liver, bile-duct and red-cell breakdown-related conditions.

Information about a low result

Low total bilirubin is usually not clinically important.

Information about a high result

High total bilirubin may occur with increased red-cell breakdown, altered bilirubin processing, liver disease or bile-duct obstruction, among other contexts.

Reference and clinical context

Start with the performing laboratory's reference interval, unit and specimen conditions. Numeric information on this page is stored as sourced example intervals or clinical thresholds.

Reference range 1

>= 0.1 – <= 1.2 mg/dL

Population: Adults
Age range: 18
Specimen: Serum / plasma

Example adult Total Bilirubin reference interval

The source presents these values as a common example reference interval. Laboratory method, age and clinical context can change the range; the user's own report takes priority.

Reference ranges may vary by laboratory, method used, age, sex, pregnancy status, and clinical context. The reference range on your own laboratory report takes precedence.

Interpretation notes

Total bilirubin alone does not identify the cause. Direct/indirect fractions and ALT, AST, ALP and GGT can add important context.

Related specialties

Gastroenterology
Internal Medicine
Hematology
Pediatrics

Frequently asked questions

Sources

Liver Function Tests — U.S. National Library of Medicine (MedlinePlus)
Government medical reference · 2026 · Liver panel components, purposes, pattern-based interpretation and limitations · Verified: Aug 12, 2026
Comprehensive Metabolic Panel — U.S. National Library of Medicine (MedlinePlus)
Government medical reference · 2026 · Example adult intervals for ALT, AST, ALP, albumin, bilirubin, total protein, BUN, creatinine and electrolytes · Verified: Aug 12, 2026
Bilirubin Blood Test — U.S. National Library of Medicine (MedlinePlus)
Government medical reference · 2026 · Total/direct bilirubin meaning, jaundice context and example intervals · Verified: Aug 12, 2026