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Gilbert's Syndrome

What is Gilbert's Syndrome?

​Gilbert's syndrome is an inherited disorder of the liver that results in an excess of bilirubin.

Most patients with Gilbert's syndrome have no symptoms. The disorder is frequently diagnosed by coincidence when a lab test done for another reason such as a life insurance examination, shows an abnormally high amount of unconjugated bilirubin.

The level of bilirubin can fluctuate in people with Gilbert's syndrome. They may be highest after an infection (such as flu), following periods of fasting, and after menstrual periods in some women.

Because males tend to produce higher levels of bilirubin, the disorder is more likely to be detected in men. Similarly, it is rarely diagnosed before puberty because production of bilirubin increases at this point.

Bilirubin is normally present in the blood in small amounts. It is a normal by-product of the breakdown of hemoglobin from old red blood cells, and it is usually converted by the liver into a form that can be excreted from the body through the bowel. Excretion of bilirubin by the liver comprises a number of steps. Abnormalities at any of these steps can cause the blood levels of bilirubin to rise above normal.

People with Gilbert's syndrome have an inherited abnormality that causes reduced production of an enzyme involved in processing bilirubin. As a result, a form of bilirubin (known as unconjugated bilirubin) accumulates in the blood, sometimes causing the yellowing of the skin or eyes.

​The diagnosis of Gilbert's syndrome is suspected in people who have persistent, slightly elevated levels of unconjugated form of bilirubin without any other apparent cause.


No specific therapy is required for patients with Gilbert's syndrome. A clinician's most important role in the management of this disorder is to reassure patients that this is a benign disorder and does not signify the presence of liver disease. Rarely, patients with Gilbert’s are at increased risk of side effects from certain drugs, particularly chemotherapy.

It may be wise to check with your doctor before taking any new medications. Care should be taken not to consume more than the recommended amount of paracetamol since people with Gilbert's syndrome may be at a greater risk for liver side-effects.

How will it affect you and your family

​People with Gilbert's syndrome live a normal, healthy life which is comparable to the general population.

As it is an inherited disorder, your children may also be affected by the same disorder.

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