Gilbert's syndrome

A harmless inherited quirk causing mild jaundice when unwell or fasting. Its main importance is not being mistaken for liver disease.

What it is

A common, entirely harmless inherited variation in the enzyme that processes bilirubin, the yellow pigment from broken-down red blood cells.

It affects around 1 in 20 people, more men than women, and most never know. Bilirubin rises slightly at times of stress on the body: fasting, dehydration, illness, exercise, sleep deprivation, alcohol, and during menstruation. When it rises enough, the whites of the eyes look slightly yellow, and it settles again.

**It is not liver disease, it does not progress, it does not damage the liver, and it requires no treatment.** Life expectancy is normal, and there is some evidence that people with it have slightly lower cardiovascular risk.

Its main importance is diagnostic. A raised bilirubin with otherwise normal liver tests and a normal blood count is the picture, and it is frequently investigated repeatedly, with scans and referrals, causing worry about a condition that is a normal variant.

The one genuinely practical implication is medication. Gilbert's affects the processing of a small number of drugs, most importantly irinotecan, a chemotherapy drug, and some HIV medicines, where dose adjustments may be needed. Anybody with Gilbert's should mention it before chemotherapy.

Paracetamol at normal doses is safe.

Signs you might notice

Mild yellowing of the whites of the eyes, coming and going.

Triggered by not eating, dehydration, illness, hard exercise, alcohol, lack of sleep, or stress.

Sometimes tiredness or vague abdominal discomfort, though whether these are caused by Gilbert's is debated and many are coincidental.

Otherwise entirely well.

Normal liver enzymes, normal blood count, and an isolated raised unconjugated bilirubin, usually below about 100 micromoles per litre.

Not Gilbert's, and needing investigation: dark urine and pale stools; itching; abdominal pain; deep or persistent jaundice; abnormal liver enzymes; anaemia; or feeling unwell. See jaundice, hepatitis and gallstones.

How it can affect day-to-day life

The most useful thing is a clear diagnosis on the record, so that a raised bilirubin found in ten years' time does not trigger another round of scans.

People are frequently told at a blood donation or an insurance medical, and worry considerably until it is explained.

The yellowing is more noticeable during illness, which is exactly when people are most likely to worry that something serious is happening.

Regular meals and staying hydrated reduce the episodes, though there is no medical need to prevent them.

Attributing fatigue to Gilbert's can be a trap: it is common, and it is worth looking for other causes such as anaemia, hypothyroidism and depression rather than settling on a harmless finding.

Family members may have it too, which explains a lot of previously unexplained mild jaundice in a family.

Supporting someone well

Get it recorded clearly on the GP record so it is not re-investigated repeatedly.

Understand that no treatment, monitoring or dietary change is needed.

Eat regularly and stay hydrated if the episodes bother you.

Mention it before chemotherapy, particularly irinotecan, and before starting HIV treatment.

Do not attribute all fatigue to it; get other causes looked for.

Get any dark urine, pale stools, itching, pain or abnormal liver enzymes investigated properly; that is not Gilbert's.

Tell family members, since it is inherited and explains similar findings in relatives.

Continue to donate blood if eligible; Gilbert's does not usually prevent it.

Where to get help

A GP practice for confirmation and for recording the diagnosis.

British Liver Trust on 0800 652 7330 have clear information on Gilbert's syndrome.