Liver Function Tests: Common Questions

Liver Function Tests: the questions people actually ask, answered from published guidance.

Key takeaways

• Common components: ALT, AST, ALP, GGT, bilirubin, albumin
• ALT and AST: markers of liver cell injury
• Most useful single change: Ask what specifically was abnormal rather than accepting "liver tests".
• Commonest mistake: Assuming normal results exclude liver disease.
• See a doctor if any of the signs under "When to get help" below apply to you.

What is Liver Function Tests?

A panel of blood tests reflecting liver injury and function.

Why does it matter?

They are frequently abnormal for benign reasons and frequently normal in significant disease, so they are a prompt rather than an answer.

Common components for Liver Function Tests?

ALT, AST, ALP, GGT, bilirubin, albumin.

ALT and AST for Liver Function Tests?

Markers of liver cell injury.

ALP and GGT for Liver Function Tests?

Markers of bile duct involvement.

Albumin and clotting for Liver Function Tests?

The only true measures of liver function.

What is the single most useful thing to do?

Ask what specifically was abnormal rather than accepting "liver tests".

What is the most common mistake?

Assuming normal results exclude liver disease.

When should I see a doctor?

Seek urgent help for yellowing of the skin or eyes, dark urine with pale stools, severe abdominal pain, vomiting blood, or confusion. Contact a GP promptly for markedly abnormal results, or for abnormal results with fatigue, itching or weight loss.

Where to go next

• The Evidence on Liver Function Tests, Without the Hype
• Why Liver Function Tests Matters, Explained Simply
• Liver Function Tests — the reference entry
• Hepatitis B and C: What the Evidence Actually Says
• What the Guidance Really Says About Cirrhosis

When to get help

Seek urgent help for yellowing of the skin or eyes, dark urine with pale stools, severe abdominal pain, vomiting blood, or confusion. Contact a GP promptly for markedly abnormal results, or for abnormal results with fatigue, itching or weight loss.

Where this comes from

• NICE — Abnormal liver blood tests clinical knowledge summary
• British Liver Trust — liver blood tests

How this page was put together

Every figure, recommendation and warning above is taken from the guidance named in Where this comes from. Nothing on this page is inferred, summarised or generalised beyond what those bodies publish: where they give a number, it is their number, and where they are silent, so are we. Pages are rebuilt whenever the underlying record changes. Sign-off by a named clinician, where it has happened, is shown at the top of the page along with the date.

Medical disclaimer

This article is general information, not medical advice. It cannot account for your own history, medication or circumstances. Always speak to a GP, pharmacist or another qualified health professional before making changes that affect your treatment, and never delay seeking medical advice because of something you have read here. In an emergency, call 999.