In the liver, it undergoes a series of chemical changes and is then excreted into bile. Next, it undergoes further chemical changes in the intestines, and from there passes out of the body. In people with Gilbert's syndrome, the bilirubin level often goes up and down. At times, it may be within the normal range. At other times, the level be higher than normal, but not dangerously so.
Scientists believe that it is an inherited disorder.
It is estimated that between three to seven percent of all adults have Gilbert's syndrome. For some people there are very few symptoms, and often they are not aware they have the disorder. However, in other people mild jaundice may appear, and the whites of the eyes may be yellowish. Others have reported gastrointestinal complaints as well as fatigue, weakness and abdominal pain. However, it is not clear whether these symptons are directly related to higher levels of bilirubin.