What causes jaundice?

Jaundice is caused by a build-up of bilirubin, often because the liver cannot process it, bile cannot drain, or red blood cells are breaking down quickly. Bilirubin is a yellow substance formed when old red blood cells are cleared. The build-up can make the whites of the eyes or skin look yellow and may darken urine or lighten stools. Jaundice is a sign rather than a diagnosis, so its cause needs assessment.

The problem may occur before bilirubin reaches the liver, within the liver, or after the liver as bile travels through the gallbladder and bile ducts. Liver inflammation from infections such as Hepatitis A can interfere with processing. Long-term liver damage, including Liver Cirrhosis, can reduce the liver's ability to handle bilirubin. A blocked bile duct may occur with inflammation of the pancreas, known as Pancreatitis, or with another blockage near the bile duct.

Faster breakdown of red blood cells can also raise bilirubin. This can happen with inherited blood conditions such as Sickle Cell Disease, or with some infections, including Malaria. Less commonly, a growth affecting the bile drainage system, such as Pancreatic Cancer or Liver Metastases, can contribute. These possibilities cannot be distinguished by colour alone; a clinician may use an examination and blood tests, with imaging when needed.

Arrange a medical assessment promptly, especially if the change is new. Note when it began and whether you have dark urine, pale stools, itching, nausea, abdominal pain, fever, weight change, or unusual tiredness. Tell the clinician about recent travel, alcohol use, prescribed medicines, supplements, previous liver problems, and any family history of blood or liver conditions. Do not stop a prescribed medicine without advice. A clinician may check bilirubin and liver enzymes, assess the blood count, and decide whether further testing is appropriate.

Seek urgent medical help if yellowing comes with severe or worsening abdominal pain, fever or chills, repeated vomiting, confusion, marked sleepiness, bleeding, or fainting. Urgent assessment is also needed if you cannot keep fluids down or if you feel acutely unwell. These symptoms can point to infection, blockage, significant liver dysfunction, or another problem that needs rapid treatment. Newborns and young infants with yellowing need prompt advice from a healthcare professional.

Useful questions include: Which tests will help identify where the bilirubin build-up is occurring? Could any of my medicines or supplements be contributing? Do my urine or stool changes suggest a bile-flow problem? What symptoms should send me to urgent care, and when should I return for the results?