Gamma-Glutamyl Transferase (GGT) in Serum/Plasma
This test measures the activity of an enzyme called gamma-glutamyl transferase, which helps your liver break down certain amino acids. It can help identify liver damage or disease.
["GGT helps detect liver issues, including alcohol-related damage or other conditions affecting bile flow."]
Key facts at a glance
- LOINC
- 108698-2
- Short code
- GABABR IgG Msmt SerPl
- Synonyms
- GABABR IgG Msmt SerPl
- Category
- coagulation
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- CPT
- 82784
- 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 This Test Matters
Your doctor may order a GGT test to check for liver problems, such as hepatitis, cirrhosis, or alcohol use. It can also help monitor conditions like bile duct blockages or certain medications that affect the liver.
What to Expect Before the Test
No special preparation is needed, but you may be asked to avoid certain medications (like some antibiotics or pain relievers) for a few days before testing. If you drink alcohol regularly, your doctor may want to discuss this with you.
Common Causes of Elevated GGT Levels
High GGT levels can occur with liver diseases (e.g., hepatitis), alcohol consumption, certain medications, or bile duct problems. Low levels are less common but may sometimes indicate liver disease in advanced stages or specific genetic conditions.
What the Results Mean
Results alone don’t diagnose a condition—they’re used alongside other tests and symptoms. Your doctor will compare your GGT level to your medical history and other test results to determine the best next steps.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Elevated GGT is often a sensitive marker of liver stress but not specific to one cause. It’s frequently used in combination with other liver tests (like ALT or AST) to guide treatment decisions, especially in cases involving alcohol exposure or drug toxicity.
Short name
GGT Level
Frequently asked questions
Why might my doctor order this test?
What does a normal GGT level mean?
Can lifestyle changes affect GGT levels?
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