GGT reference ranges
| Group | Normal Range |
|---|---|
| Men | 10–71 U/L |
| Women | 6–42 U/L |
| Mild elevation | 2–3x upper limit |
| Significant elevation | >3x upper limit |
What does high GGT mean?
Causes of raised GGT
GGT is the most sensitive liver enzyme for alcohol intake — even moderate regular drinking raises GGT. Other causes include non-alcoholic fatty liver disease (NAFLD), bile duct obstruction, liver inflammation (hepatitis), certain medications (phenytoin, carbamazepine, statins), and thyroid disease. GGT alone is not diagnostic — it is always interpreted alongside ALT, AST and ALP to identify the pattern of liver disease.
GGT and alcohol
GGT is widely used as a marker of alcohol use. It rises after as little as 3–4 drinks per day and normalises within 2–6 weeks of stopping alcohol. A raised GGT with normal ALT and AST in the context of alcohol use is a common finding. If GGT is raised alongside ALT/AST, liver cell damage is more likely.
GGT with other liver tests
| Pattern | Likely cause |
|---|---|
| GGT raised, ALT/AST normal | Alcohol use, medication effect, fatty liver |
| GGT + ALT/AST raised | Hepatitis, significant liver disease |
| GGT + ALP raised | Bile duct obstruction, cholestasis |
| All liver tests raised | Significant liver disease — needs full workup |
Questions to ask your doctor
- Is my GGT elevation from alcohol or another cause?
- Do I need an ultrasound of my liver?
- Should I reduce alcohol intake and recheck?
Medical Disclaimer: For educational purposes only. Always consult a qualified healthcare professional for diagnosis and treatment.