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GGT A sensitive liver enzyme that rises with alcohol

Also called Gamma-glutamyl transferase, Gamma-GT and GGTP Not on a standard checkup Fast for 8 hours

The short answer

GGT is an enzyme from your liver and bile ducts. It’s one of the most sensitive signs that something is straining your liver, often alcohol or fatty liver, but it can’t tell you what.2 Labcorp flags results above 65 IU/L for men and 60 for women.9

A good result
65 IU/L or under for men, and 60 or under for women.9
If yours is high
Alcohol and extra weight are the usual reasons.2 When alcohol is the cause and the liver isn’t damaged, GGT is usually back to normal 2 months after stopping.5
Should you test?
Not as a screen on its own. It’s most useful when your ALP is high, or as one clue to heavy drinking alongside other tests.1

Check your result

Type the number from your report. It stays on this page.

Which fits you?
66 195
  • Normal Under 66
  • Raised 66 to 194
  • High 195 or more

Enter your result to see what it means and what to do next.

Got a result from another lab? Ask Picardo about it. The app explains your results, and a physician can follow up.

Ranges are Labcorp’s.9 The top band starts at 3 times Labcorp’s upper limit. In a large Finnish study, the risk of serious liver disease climbed most above 3 times that study’s own upper limit.8 The bar isn’t to scale.

What is a normal GGT level?

Labcorp flags GGT above 65 IU/L for men and 60 for women.9 On its own, a raised GGT isn’t a diagnosis. What matters is the cause:1

Normal 65 IU/L or under for men; 60 or under for women

In the normal range

Your GGT is within Labcorp’s range.9 A normal GGT doesn’t rule out heavy drinking, though: it’s raised in only about half of heavy drinkers who don’t have liver disease.1,5

How worried to be

Nothing to worry about.

What to do next
  1. 1 If your ALP is high, a normal GGT points to bone rather than the liver as the source.1,2
Raised 66 to 194 IU/L for men; 61 to 179 for women

Raised: find the cause

Your GGT is above Labcorp’s range.9 It’s a sensitive sign but not a specific one. The common causes are alcohol, extra weight and some medicines, such as the seizure drugs phenytoin and phenobarbital.1,2,9

How worried to be

Not urgent. Worth finding the cause over the next few weeks.

What to do next
  1. 1 Look at your ALT, AST and ALP. A raised GGT means more when other liver tests are raised too.1
  2. 2 If you drink heavily, stop for 8 weeks and retest. In heavy drinkers without liver disease, GGT was back to normal in 80% of those who stopped.5
  3. 3 If you drink and your GGT is over 100, ask about a check for liver scarring.2
High 195 IU/L or more for men; 180 or more for women

High: see a clinician soon

That’s at least 3 times Labcorp’s upper limit.9 In a Finnish study of more than 20,000 adults, people whose GGT was over 3 times that study’s upper limit (above 144 U/L for men and 225 for women) had about a 9% chance of a serious liver problem within 10 years.8 Common causes are heavy drinking, blocked or inflamed bile ducts and liver disease.1,2

How worried to be

See a clinician in the next couple of weeks. It isn’t an emergency.

What to do next
  1. 1 Get your other liver tests, including ALT, AST, ALP and bilirubin, if you don’t have them.1
  2. 2 If you drink, stopping is the most useful step. If GGT is still high after 8 weeks without alcohol, something else may be keeping it up, and liver damage is one possibility.5
Heart Health panel
$150.90 · GGT plus 16 more tests, one visit
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Or order GGT on its own, $3.25

What is GGT?

GGT is like a very sensitive smoke alarm. It goes off for a fire, but also for burnt toast. It tells you to look, not what you’ll find.

GGT, short for gamma-glutamyl transferase, is an enzyme found mostly in the liver and bile ducts, and also in the kidneys, pancreas, intestines and prostate. It isn’t found in bone, which makes it useful for working out where a raised ALP is coming from.2

Adding GGT to routine liver tests doubles the share of adults with an abnormal result, from about 15% to 30%.2 Because so much raises it, US guidelines don’t use it on its own to screen for liver disease.1 UK guidelines include it in the first round of liver tests, since a raised GGT predicts deaths from liver disease.2

Does GGT show how much you drink?

Partly. GGT is a long-standing clue to heavy drinking, but guidelines say it varies too much from person to person to rely on alone.1,4 It isn’t specific: extra weight, diabetes and some medicines raise it too.1,2 And it misses many heavy drinkers. In one study it was raised in only about half of those without liver disease.5

When alcohol is the cause, GGT falls once you stop. In heavy drinkers without liver disease, it was back to normal in 80% after 8 weeks without alcohol. In those with liver disease, it stayed high.5

To measure drinking itself, a newer blood test does better. Phosphatidylethanol (PEth) reflects drinking over roughly the past month.4

What raises GGT?

  • Alcohol1,3
  • Extra weight and fatty liver2
  • Medicines, including the seizure drugs phenytoin and phenobarbital1,9
  • Blocked or inflamed bile ducts2
  • Diabetes, pancreatic disease, kidney failure, heart attacks and emphysema1

Is a high GGT bad for your health?

In a review of long-term studies, people in the top third for GGT had a 60% higher risk of dying during follow-up than those in the bottom third.6 Whether GGT itself harms the heart is unsettled: a genetic study that tested this couldn’t rule it in or out.7 UK guidelines note that a raised GGT most often reflects extra weight or alcohol, and that it’s one of the best predictors of dying from liver disease.2

How to lower GGT

  • Stopping or cutting back on alcohol

    In heavy drinkers without liver disease, GGT was back to normal 8 weeks after stopping in 80% of them.5

    How much it helps
    A lot
    How sure we are
    Very sure
  • Losing extra weight

    Extra weight and fatty liver are among the most common reasons for a raised GGT.2

    How much it helps
    Some
    How sure we are
    Early evidence
  • Reviewing your medicines

    Some drugs, such as phenytoin and phenobarbital, raise GGT on their own. Ask before stopping a prescribed medicine.1,9

    How much it helps
    Some
    How sure we are
    Fairly sure

Who should get a GGT test?

GGT isn’t a screening test on its own.1 It’s most useful:

  • When your ALP is high, to tell whether it’s coming from the liver or from bone.1,2
  • As one clue to heavy drinking, and to see whether cutting back is working.5,9
  • When other liver tests are abnormal, to help find the cause.1

How to get a GGT test, and what it costs

A GGT test costs $3.25 through Picardo. The Heart Health panel adds 16 more tests from the same visit for $150.90.

Recommended

Heart Health panel

$150.90
17 tests · fast for 12 hours first

GGT is one clue. The panel adds ALT, AST and ALP, a platelet count for a FIB-4 scarring score, and the blood sugar and cholesterol tests that go with fatty liver. See what’s in it

Order the Heart Health panel
Just this test

GGT on its own

$3.25
Labcorp 001958 · fast for 8 hours

Only the number this page is about.

Order GGT
  • Results in 2 to 3 days, in the app
  • Physician follow-up if you want one
  • Free Labcorp draw, or $75 at home
  • No other fees. HSA and FSA eligible.
Already have a result? Ask Picardo about it

Questions people ask

Can GGT be high if I don’t drink?

Yes. Extra weight and fatty liver are among the most common causes, and diabetes and some medicines raise it too.1,2

Why is my GGT high when my other liver tests are normal?

It’s common, because GGT is more sensitive than the other tests. Guidelines don’t use GGT on its own to screen for liver disease, since so many things raise it.1 Look at alcohol, weight and medicines first.1,2

Do medicines raise GGT?

Some do. The seizure drugs phenytoin and phenobarbital are the best known; Labcorp suggests other tests for people taking them.1,9

Do I need to fast for a GGT test?

Labcorp asks for an 8-hour fast before a GGT test.9

Often checked alongside

ALT
The enzyme most specific to liver damage
ALP
An enzyme from liver and bone
AST
An enzyme from liver and muscle
Ferritin
How much iron you have in store

Test details

Labcorp test
γ-Glutamyl Transferase (GGT), 001958
LOINC
2324-2
Sample
Blood
Fasting
8 hours, per Labcorp9
Typical lab range
0 to 65 IU/L (men); 0 to 60 IU/L (women)9
Units
IU/L, the same as U/L

Sources

  1. 1 Kwo PY, Cohen SM, Lim JK. ACG clinical guideline: evaluation of abnormal liver chemistries. Am J Gastroenterol. 2017;112(1):18–35. doi.org/10.1038/ajg.2016.517
  2. 2 Newsome PN, Cramb R, Davison SM, et al. Guidelines on the management of abnormal liver blood tests. Gut. 2018;67(1):6–19. doi.org/10.1136/gutjnl-2017-314924
  3. 3 Crabb DW, Im GY, Szabo G, et al. Diagnosis and treatment of alcohol-associated liver diseases: 2019 practice guidance from the American Association for the Study of Liver Diseases. Hepatology. 2020;71(1):306–333. doi.org/10.1002/hep.30866
  4. 4 Jophlin LL, Singal AK, Bataller R, et al. ACG clinical guideline: alcohol-associated liver disease. Am J Gastroenterol. 2024;119(1):30–54. doi.org/10.14309/ajg.0000000000002572
  5. 5 Moussavian SN, Becker RC, Piepmeyer JL, et al. Serum gamma-glutamyl transpeptidase and chronic alcoholism: influence of alcohol ingestion and liver disease. Dig Dis Sci. 1985;30(3):211–214. doi.org/10.1007/BF01347885
  6. 6 Kunutsor SK, Apekey TA, Seddoh D, Walley J. Liver enzymes and risk of all-cause mortality in general populations: a systematic review and meta-analysis. Int J Epidemiol. 2014;43(1):187–201. doi.org/10.1093/ije/dyt192
  7. 7 Liu J, Au Yeung SL, Lin SL, et al. Liver enzymes and risk of ischemic heart disease and type 2 diabetes mellitus: a Mendelian randomization study. Sci Rep. 2016;6:38813. doi.org/10.1038/srep38813
  8. 8 Åberg F, Jula A, Salomaa V, et al. Updated reference limits for liver blood tests with validation against long-term liver-related outcomes. Liver Int. 2025;45(12):e70440. doi.org/10.1111/liv.70440
  9. 9 Labcorp. γ-Glutamyl transferase (GGT), test 001958. Labcorp test menu. Accessed October 28, 2026. www.labcorp.com/tests/001958/glutamyl-transferase-ggt

Updated 28 Oct 2026.

This is general health information, not medical advice: talk to your clinician about your results and before changing any treatment.