Gilbert Syndrome is a hereditary disorder of hepatic bilirubin metabolism occurring in about 5 to 7% of population around the world. It is relatively common in Americans and Europeans. It is caused by relative deficiency of glucuronyl transferase (UGT) enzyme. UGT is responsible for converting unconjugated or free bilirubin (fat-soluble) to water soluble unconjugated bilirubin, which is then excreted out of the body through feces.


What Are The Causes And Symptoms Of Gilbert Syndrome?

As mentioned above, Gilbert Syndrome is caused by inherent deficiency of glucuronyl transferase enzyme. It is passed from parents to offspring through autosomal dominant pattern, means both the parents should have the copy of gene deficient in UGT enzyme.


Jaundice or yellowing of the eyes and skin is the only classical symptom observed in Gilbert syndrome, which is due to elevated levels of bilirubin in the blood due to incomplete excretion of bilirubin by the body. Some people with Gilbert syndrome may even complain of fatigue and abdominal discomfort. Various factors can precipitate Gilbert syndrome and these include stress, dehydration, fasting, starvation, excessive exercise and exertion, infections such as viral, alcohol, certain medications, surgery and excessive menstruation.


What Are The Diagnosis And Treatment Of Gilbert Syndrome?

Most of the times, Gilbert syndrome goes unnoticed and sometimes does not even get diagnosed until the age of 20 or 30. It is, generally, diagnosed inadvertently and tests show increased level of bilirubin in blood. Other tests might be done to rule out any other liver condition or disease. Gene tests can also be carried out for the diagnosis of Gilbert syndrome.

Gilbert syndrome is a benign condition and usually does not require any treatment. However, certain measures can be taken to avoid elevated levels of bilirubin. These include staying hydrated, avoiding fasting or starvation, eating regular meals, avoiding stress (physical or emotional), sleeping regularly and avoiding insomnia and avoiding alcohol. Individuals should eat healthy food rich in fruits and vegetables.

What Drugs To Avoid When You Have Gilbert Syndrome?

There are certain drugs than one should avoid, when one has Gilbert syndrome, as the patient is deficient in UGT enzyme responsible for processing bilirubin. There may be complications after ingesting certain medications that are processed in the same pathway as bilirubin or medications that inhibit UGT enzyme leading to toxicity. The medications that should be avoided by Gilbert Syndrome individuals include certain antiviral drugs such as atazanavir (Reyataz) and indinavir (Crixivan) that are used to treat HIV infection and/or hepatitis C. These individuals should also avoid irinotecan (Camptosar), a drug used in the treatment of advanced bowel cancer along with gemfibrozil (Lopid) that is a drug used in hypercholesterolemia. Statins are partly metabolized by UGT enzyme, so one should consult his/her doctor before taking these medications if they have Gilbert Syndrome to avoid any adverse effects.

Although, paracetamol is not metabolized by glucuronyl transferase, it is metabolized by another enzyme, which is also deficient in few individuals of Gilbert syndrome that puts these individuals at a greater risk of developing paracetamol toxicity. Anesthetics like morphine should also be avoided in Gilbert syndrome cases when they are prepared for surgery. Morphine has been known to cause prolonged anesthetic effect on individuals with Gilbert syndrome, since it is also metabolized in liver by glucuronidation, but with different isoform of UGT enzyme. There are still conflicting studies regarding the effects of morphine in Gilbert syndrome cases, so it should be best avoided as a precaution, incase told otherwise. Other drugs that are processed by glucuronidation include codeine, temazepam and testosterone. Certain herbal supplements including cranberry, gingko biloba, hawthorn, noni, soy, grape seed, milk thistle, valerian and green tea are rich in chemicals that can modulate UGT enzyme; however, there interaction is not well understood. It is best to consult a doctor before taking any medication or herbal supplements to avoid any side effect or adverse effect.

Also Read:

Pramod Kerkar

Written, Edited or Reviewed By:


Pain Assist Inc.

Last Modified On: August 1, 2018

This article does not provide medical advice. See disclaimer


Sign Up for Our Newsletter

We'll help you live each day to the healthiest