Gammaglutamyltransferase (GGT) in serum/plasma
This test measures the enzyme GGT, which helps assess liver function and detect potential liver damage or disease.
["GGT can indicate liver issues, including alcohol-related damage or other conditions affecting bile flow."]
Key facts at a glance
- LOINC
- 12253-1
- Short code
- GH BS SerPl-mCnc
- Synonyms
- GH BS SerPl-mCnc
- Category
- chemistry
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Specimen volume
- 5 mL
- Stability
- Room temperature: 4h, Refrigerated: 24h, Frozen: 7d
- Hemolysis max
- 500
- Lipemia max
- 1000
- Icterus max
- 500
- TAT
- 4–24 hours
- Order
- routine
Why Is This Test Done?
Doctors may order a GGT test to evaluate symptoms like jaundice (yellowing of skin/eyes), abdominal pain, or unexplained fatigue. It’s also used alongside other liver tests to monitor conditions like hepatitis, cirrhosis, or bile duct blockages. Sometimes, it’s checked during routine health screenings or before certain treatments.
What Does a High or Low GGT Level Mean?
Elevated GGT levels often suggest liver problems, such as alcohol use, fatty liver disease, or infections like hepatitis. However, other factors like certain medications, heart disease, or kidney issues can also influence results. Low GGT levels are less common but may occur in rare genetic conditions or during pregnancy.
How Is the Test Performed?
A blood sample is drawn from a vein in your arm. You may feel a slight pinch, but it usually doesn’t cause discomfort. The sample is sent to a lab for analysis using a specialized method to measure GGT activity.
What Should You Know Before Testing?
If you’re taking medications (like antibiotics, painkillers, or certain heart or blood pressure drugs), inform your doctor, as they may affect results. Avoid heavy alcohol consumption for at least 24 hours before testing, as it can raise GGT levels.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
GGT is a sensitive marker for liver damage, often rising before other liver enzymes (like ALT or AST) do. It helps doctors distinguish between different liver conditions, such as alcohol-related liver disease versus viral hepatitis. Additionally, GGT can be monitored over time to track the progression or response to treatment of liver-related illnesses.
Short name
GGT
Frequently asked questions
How long does it take to get results?
Can lifestyle changes affect GGT levels?
Is there anything I should avoid before this test?
Sources
- 1
- 2Lab Tests OnlineSource
- 3
Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.
This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.
If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.
Medically reviewed by WellAlly Editorial Team Last reviewed August 16, 2026. · Read our editorial policy