LFT Biomarker
Collection Type: Blood
Related System: LFT
Gamma‑glutamyl transferase (GGT) is an enzyme found mainly in liver cells and biliary epithelium; the blood test measures circulating GGT activity. It is a sensitive marker of hepatobiliary injury and enzyme induction rather than a specific disease test. Elevated GGT suggests cholestasis (bile duct obstruction), alcoholic liver disease, non‑alcoholic fatty liver disease, or drug‑induced liver enzyme induction; modest isolated rises commonly reflect alcohol use or enzyme‑inducing medications. Symptoms that prompt testing include jaundice, dark urine, pale stools, pruritus, abdominal pain, fatigue or unexplained abnormal liver tests. Normal GGT varies by age and sex (higher in adult males) and can be higher in older adults and in people who consume alcohol or certain drugs.
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Symptom CheckerMale: 8-61 U/L; Female: 5-36 U/L
Q: What does it mean when your GGT is high?
A: A high GGT (gamma‑glutamyl transferase) usually signals liver or bile‑duct stress: cholestasis, obstruction, fatty liver, hepatitis, or damage from alcohol or certain drugs. It’s a sensitive but non‑specific marker—levels rise with alcohol use, enzyme‑inducing medicines, or other systemic illnesses. Doctors interpret GGT alongside AST/ALT/ALP, imaging, and history to find the cause and guide further tests or treatment.
Q: Can GGT return to normal?
A: Yes. Gamma‑glutamyl transferase (GGT) often returns to normal if the underlying cause is treated—stopping alcohol, changing offending drugs, weight loss, controlling metabolic disease, or treating biliary or liver conditions. Improvement may take weeks to months. Persistent elevation suggests chronic liver or bile‑duct disease and warrants further evaluation and repeat testing with your clinician.
Q: What is the treatment for high GGT levels?
A: Treatment targets the underlying cause: stop alcohol and hepatotoxic drugs; lifestyle changes (weight loss, glycemic and lipid control, healthy diet, smoking cessation); treat specific liver or biliary disease (antivirals for viral hepatitis, ursodeoxycholic acid, endoscopic/surgical relief for obstruction); review and adjust medications; monitor liver tests. See a clinician for diagnosis, tailored therapy and follow-up.
Q: What is the normal range of GGT by age?
A: Normal GGT ranges vary by age and sex. Neonates are often elevated and variable. Infants/children: about 4–30 U/L. Adult females: ~5–36 U/L. Adult males: ~7–51 U/L. Older adults may have slightly higher upper limits (up to ~60 U/L). Medications, alcohol use and liver disease can raise GGT; always use the lab’s reference interval.
Q: Is high GGT due to fatty liver?
A: Yes fatty liver (nonalcoholic or alcoholic) can raise GGT, but an elevated GGT is non‑specific. It can also reflect alcohol use, bile-duct problems, medications or other liver disease. Doctors interpret GGT alongside ALT/AST, imaging and clinical history. Evaluation may include ultrasound and metabolic workup; management focuses on weight loss, blood‑sugar and lipid control, and reducing alcohol.
Q: Is GGT a tumor marker?
A: GGT (gamma‑glutamyl transferase) is not a specific tumor marker. It’s a liver/biliary enzyme often raised with alcohol use, cholestasis, liver injury and some cancers (eg, hepatobiliary tumors), but elevations are nonspecific. GGT alone cannot diagnose cancer; it may support further investigation alongside imaging, disease-specific tumor markers and clinical assessment. Interpretation requires clinical context and correlation with other tests.