Gamma-glutamyl transpeptidase (GGT) is a test to measure the amount of the
Gamma-GT; GGTP; GGT
How the test is performed
A blood sample is taken from a vein. This is called a
How to prepare for the test
The health care provider may tell you to stop taking any drugs that can affect the test.
Drugs that can increase GGT levels include:
Drugs that can decrease GGT levels include:
- Birth control pills
How the test will feel
When the needle is inserted to draw blood, some people feel moderate pain, while others feel only a prick or stinging sensation. Afterward, there may be some throbbing.
Why the test is performed
This test is used to detect diseases of the liver or
It may also be done to screen for or monitor alcohol abuse.
The normal range is 0 to 51 international units per liter (IU/L).
Note: Normal value ranges may vary slightly among different laboratories. Talk to your doctor about the meaning of your specific test results.
The examples above show the common measurements for results for these tests. Some laboratories use different measurements or may test different specimens.
What abnormal results mean
Greater-than-normal levels of GGT may be due to:
Flow of bile from the liver is blocked (
cholestasis) Heart failure Hepatitis
- Liver ischemia (lack of blood flow)
- Liver tumor
- Lung disease
- Pancreas disease
- Scarring of the liver (
- Use of drugs that are toxic to the liver
What the risks are
There is very little risk involved with having your blood taken. Veins and arteries vary in size from one patient to another and from one side of the body to the other. Taking blood from some people may be more difficult than from others.
Other risks associated with having blood drawn are slight but may include:
- Bleeding from where the needle was inserted
- Fainting or feeling light-headed
- Hematoma (blood collecting under the skin)
- Infection (rare)