Home › Biomarkers › Bilirubin, direct
Bilirubin, direct, also called conjugated bilirubin, is one of the measurements of bilirubin in your blood. A high level can point to a liver condition, a blockage in the bile ducts or red blood cells breaking down too quickly; a low level is usually no cause for concern.[1]
On this page you can read what bilirubin, direct is, what the guidelines say about a level that is too low or too high, what affects your level and which values are best to look at alongside it.
Also known as: direct bilirubin, conjugated bilirubin. At the lab: BILD.
Bilirubin is a yellowish substance. Your body makes it during the normal breakdown of old red blood cells. Bilirubin is found in bile, a fluid your liver makes to help you digest food.[1]
If your liver is healthy, it removes most bilirubin through the bile ducts. These are the small tubes that carry bile out of your liver. If your liver is damaged or the bile ducts are blocked, bilirubin can leak into your blood. Too much bilirubin in your blood can turn your skin and eyes yellow.[1]
Bilirubin, direct, also called conjugated bilirubin, is one of the names under which the lab measures bilirubin. Bilirubin is usually measured in blood, but it can also be tested in urine.[1]
With a bilirubin test, a doctor can look at the health of your liver. The test also helps to find the cause of yellow skin and yellow eyes. And it shows how a value changes during care.[1]
A doctor may order the test if you have symptoms such as dark urine, clay-coloured stools or abdominal pain. These symptoms can point to a liver condition. The test also helps to see whether there is a blockage in your bile ducts.[1]
In newborn babies, bilirubin is often measured as a precaution. Many healthy babies get yellow skin because their liver is not yet developed enough. This is usually not harmful and fades within a few weeks.[1]
Labplusarts, the lab BioProfile works with, uses a reference value of 0 to 4 umol/l for bilirubin, direct. The lab calls a value between those limits normal.[2]
| Value | What it can mean | Who it is for |
|---|---|---|
| 0 to 4 umol/l[2] | Between the limits: the lab calls this normal | The lab does not name a separate group |
Source: Labplusarts, the lab BioProfile works with. Reference value for bilirubin, direct (BILD).[2]
According to MedlinePlus, a low bilirubin is usually no cause for concern. A low level can, however, point to the use of certain medicines, such as antibiotics, the contraceptive pill, sleeping pills and medicines for seizures.[1]
A high bilirubin can point to a liver that is not working properly. It can also point to a liver condition, a blockage in the bile ducts or a form of anaemia in which your body breaks down red blood cells faster than it makes them. An abnormal result does not always mean there is something you need care for. If your result falls outside the lab's range, further tests may be needed.[1]
BioProfile is working on its own zones for each value, from risk to optimal. A doctor reviews those zones before they appear in your result.
Some medicines can raise your bilirubin, others can lower it. Tell your doctor which medicines you take. Never stop a medicine on your own, only when your doctor tells you to.[1]
Certain foods can raise your bilirubin. That is why your doctor may ask you not to eat or drink for a number of hours before your blood is taken.[1]
Heavy exercise can also give a higher bilirubin than normal.[1]
What is normal can vary by lab, by sex, and between adults and children or babies.[1]
Bilirubin, direct is included in BioProfile 121 and 150.[3]
The BioProfile editorial team wrote this page on 10 October 2026 from the sources below, which we read on 10 October 2026. Every number on this page appears in one of those sources, with that source's number next to it. An expert has yet to check this page; after that check, the expert's name and the date of the check will appear at the top. This page offers explanation, not a diagnosis. Discuss a value outside the range with your GP.
