Liver · Blood test
GGT (gamma GT) test: normal range explained
Also printed as: Gamma GT, Gamma Glutamyl Transferase, GGTP
GGT, or gamma-glutamyl transferase, is an enzyme concentrated in the liver and bile ducts, and the blood test measures how much has leaked into your blood. The adult range commonly printed on Indian reports is 9–48 U/L, inside the under 50 U/L that Testing.com quotes, but the range printed on your own report is the one that applies.
Last updated 3 sources
What is the normal range for GGT?
| Printed for | Range |
|---|---|
| Adults, varies by sex | 9–48U/L |
Reference ranges vary between laboratories. Always use the range printed on your own report. Why ranges differ between labs
Sources:Testing.com
What does GGT measure?
GGT is an enzyme found throughout the body but mainly in the liver. When the liver or bile ducts are damaged, GGT leaks into the blood, so a high level suggests liver or bile duct trouble without saying what caused it.
GGT can be more sensitive than ALT and AST for liver damage from medicines, obesity and alcohol, and most people with alcohol use disorder have a raised level.
Sources:MedlinePlus, Lab Tests Online UK
Why do doctors order the GGT test?
Doctors order GGT to help diagnose liver disease, to check for a blocked bile duct, and to screen for or monitor alcohol use. It is usually ordered with or after an alkaline phosphatase (ALP) test: both rise with liver and bile duct disease, but only ALP rises with bone disease, so comparing them shows whether a problem is in the liver or in bone.
It may also follow an abnormal ALP or other liver results, or symptoms such as tiredness, jaundice, poor appetite, belly pain, nausea or severe itching.
Sources:MedlinePlus, Testing.com
What can change your GGT result?
GGT reacts to alcohol, several medicines, smoking and meals, so the days before the test matter.
- Alcohol raises GGT, and Testing.com advises avoiding it for 24 hours before the test.
- Phenobarbital, phenytoin and warfarin are named as medicines that can raise GGT, and many others can affect it. Do not stop a medicine unless your doctor tells you to.
- Cigarette smoking pushes GGT higher.
- GGT levels fall after meals, so a lab may ask you to fast; Testing.com asks for eight hours with water allowed.
- Higher body weight, metabolic syndrome and type 2 diabetes are linked with higher GGT even without heavy drinking.
- Ranges vary by lab, age and sex, so the row printed for you may differ from a family member's.
Sources:MedlinePlus, Testing.com
How do you read GGT on your lab report?
GGT is printed as GGT, Gamma GT, GGTP or gamma-glutamyl transpeptidase on a liver function test, in U/L, usually near ALP, with the lab's range beside it. Some labs print separate rows for women and men.
Read it with ALP: a high ALP with a high GGT points towards the liver or bile ducts, while a high ALP with a normal GGT makes bone more likely. A low or normal GGT makes liver disease less likely but does not rule it out.
Amara reads GGT with the range printed beside it on each report, flags a value outside that range, and shows what changed since your last report. Try it with two sample reports
A sample Amara row for GGT: 53 U/L on 28 Jan 2026 at Lab A (sample), then 34 U/L on 16 Aug 2026 at Lab B (sample), each with its lab's printed range.
Sources:MedlinePlus, Testing.com
Questions people ask about GGT
Is GGT the same as GGTP?
GGT and GGTP are the same test. GGT is short for gamma-glutamyl transferase, and GGTP for gamma-glutamyl transpeptidase, an older name for the same enzyme; MedlinePlus also lists gamma-GT and GTP as other names. Indian reports use any of these labels, so read the value against the range printed beside it.
Do I need to fast or avoid alcohol before a GGT test?
Fasting is often requested for GGT because levels fall after meals; Testing.com asks for eight hours without food, with water allowed, and MedlinePlus says your provider may set a fasting period. Testing.com also advises no alcohol for 24 hours before the draw, since alcohol raises GGT. Follow the instructions on your own form.
What can a high GGT result mean on my report?
A high flag on GGT means the value sits above the range that lab printed. MedlinePlus lists hepatitis, cirrhosis, alcohol use, pancreatitis, diabetes, heart failure and medicine side effects as reasons a doctor considers, and smoking and higher body weight also push it up. Your doctor reads it with ALP and the other liver values.
Why is GGT not always part of a liver function test?
GGT is not in every liver profile. Lab Tests Online UK describes the standard liver panel as up to five tests and lists GGT separately, as an extra test that helps when ALP is raised or when alcohol or medicines may be affecting the liver. If your report has no GGT row, your doctor can add it.
Sources
- Gamma-glutamyl Transferase (GGT) TestMedlinePlus · medlineplus.gov · Opened
- Gamma-Glutamyl Transferase (GGT) Test: Check Liver HealthTesting.com · testing.com · Opened
- Liver Blood TestsLab Tests Online UK · labtestsonline.org.uk · Opened
About this page
Every statement on this page comes from the sources listed above. Ranges are those commonly printed on Indian lab reports; the range printed on your own report is the one that applies.
Published by Amara Health, a product of MetaNova AI Private Limited, Hyderabad.
Amara Health does not provide medical advice, diagnosis or treatment. Information shown by Amara is based on available health records and may contain errors. Review important information against the original report and consult a qualified healthcare professional for medical decisions. Do not use Amara for medical emergencies.
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