Also seen on reports as: Total Bilirubin, Direct Bilirubin, Indirect Bilirubin, Conjugated Bilirubin, Unconjugated Bilirubin
What is Bilirubin?
Bilirubin is a yellow-orange pigment formed when the body breaks down old red blood cells. The liver picks up bilirubin from the blood, processes it (this is called conjugation), and sends it out into the bile and then into the gut, where most of it leaves the body in stool.
Lab reports typically show three values: Total Bilirubin (all of it), Direct Bilirubin (the conjugated, liver-processed form), and Indirect Bilirubin (the unconjugated, not-yet-processed form). Total = Direct + Indirect. The pattern of which fraction is raised gives doctors a clue about where in this pathway the problem lies.
The test is run on a small blood sample drawn from a vein. NABL-accredited Indian labs report bilirubin in milligrams per decilitre (mg/dL).
Why doctors order it
Bilirubin is part of the standard Liver Function Test (LFT) panel ordered in routine health checks, when symptoms suggest liver or bile-duct involvement (yellowing of eyes or skin, dark urine, pale stools, persistent itching, right-upper-abdomen pain), and as part of pre-operative work-up.
In Indian practice, bilirubin is also commonly checked during acute illness — particularly tropical infections like hepatitis A and E (which are still very common in India and easily spread through contaminated water or food), dengue, malaria, leptospirosis, and typhoid. All of these can raise bilirubin acutely.
Newborn bilirubin is measured separately, often by skin meter and sometimes by blood, to detect and treat newborn jaundice. Adult bilirubin reference ranges do not apply to newborns — IAP (Indian Academy of Pediatrics) has separate protocols.
What the result means
Mild isolated raised Indirect Bilirubin (with normal liver enzymes and normal Direct Bilirubin) is most commonly Gilbert's syndrome — a benign, genetic, lifelong condition that affects an estimated 5–10% of Indians. It causes mild jaundice that worsens with fasting, illness, or stress, but does not damage the liver and does not need treatment.
Raised Direct Bilirubin, or raised Total Bilirubin with both fractions involved, usually points to liver-cell injury (hepatitis from any cause) or to a problem with bile drainage (gallstones, bile-duct obstruction). Pale stools and dark urine, alongside raised Direct Bilirubin, suggest bile-flow obstruction more strongly.
Acutely raised bilirubin in a tropical illness setting is more often due to the infection itself or to drug effect than to a structural liver problem — common causes seen in Indian practice include hepatitis A and E, dengue, malaria, leptospirosis, and antibiotic or anti-malarial side effects. The pattern of LFTs and ultrasound findings help differentiate.
Reference range
Values in mg/dL. Adult reference ranges; newborn ranges are different and managed separately.
- Total Bilirubin — normal
- Roughly 0.1 – 1.2 mg/dL
- Direct (Conjugated) Bilirubin
- Roughly 0.0 – 0.3 mg/dL
- Indirect (Unconjugated) Bilirubin
- Roughly 0.2 – 0.8 mg/dL (calculated: Total − Direct)
- Clinical jaundice (yellowing visible)
- Usually appears when Total Bilirubin >2.0–2.5 mg/dL
- Gilbert's syndrome pattern
- Mildly raised Total / Indirect with normal Direct and normal liver enzymes
Newborn bilirubin uses entirely different reference ranges and is managed by IAP protocols. Adult bilirubin is read alongside the rest of the LFT panel — bilirubin alone is rarely interpreted in isolation.
In India
What this test means for an Indian reader
Gilbert's syndrome — a benign genetic cause of mild unconjugated hyperbilirubinemia — is estimated to affect 5–10% of Indians and explains many incidentally raised bilirubin findings during routine checks. Acute bilirubin elevation in India also often reflects tropical infections (hepatitis A/E, dengue, malaria, leptospirosis) rather than chronic liver disease.
Indian guidelines & references
- Indian National Association for Study of the Liver (INASL)
- Indian Academy of Pediatrics (IAP) — neonatal jaundice protocols
Common factors that affect the result
Fasting (particularly prolonged fasts) raises Indirect Bilirubin in people with Gilbert's syndrome and can mildly raise it in others — this is one reason lab samples are usually drawn after a normal overnight fast, not an extended one. Acute illness, infection, intense stress, and recent strenuous exercise can also nudge bilirubin upward.
Several medications can affect bilirubin. Antibiotics (some cephalosporins, fluoroquinolones), anti-TB drugs (rifampicin in particular shifts bilirubin handling), and a variety of pain medications can produce raised values. Ayurvedic and herbal supplements have been documented to cause cholestatic (bile-flow) injury with raised Direct Bilirubin.
Haemolysis — increased breakdown of red blood cells — raises Indirect Bilirubin without involving the liver. This happens in some genetic anaemias (thalassaemia, G6PD deficiency), in malaria, in transfusion reactions, and in some autoimmune conditions. Doctors usually check haemoglobin, LDH, and reticulocyte count alongside.
When to talk to your doctor
- Your Total Bilirubin is above the upper limit and Direct Bilirubin is also raised — this usually warrants liver and bile-duct evaluation.
- You have visible yellowing of the eyes or skin, dark (cola-coloured) urine, or pale clay-coloured stools — these need prompt medical attention.
- You have an acute febrile illness with raised bilirubin — particularly during dengue season, hepatitis outbreaks, or after travel to areas with malaria or leptospirosis risk.
- You are on tuberculosis medication, anti-seizure medication, or chemotherapy, and your bilirubin has risen — this may need a dose review.
- You have a known pattern of mild raised Indirect Bilirubin with normal liver enzymes (Gilbert's syndrome) and want to confirm it does not need ongoing monitoring beyond routine care.
Related tests
Sources
- INASL Position Statements on Liver Function Test Interpretation — Indian National Association for Study of the Liver
- Indian Academy of Pediatrics (IAP) — Newborn Jaundice Protocols — Indian Academy of Pediatrics
- ICMR National Viral Hepatitis Control Programme — Indian Council of Medical Research
- AASLD Guidelines on Abnormal Liver Tests — American Association for the Study of Liver Diseases
- WHO Guidelines on Hepatitis Testing — World Health Organization
See our medical disclaimer for what this content is and is not.