#liverdisease #liver #liverhealth #ggt #ggtp #hepatitisb #hepatitistest #hepatitis #sgot GGT Levels Over 500 - Severe Liver and Bile Duct Dysfunction Normal Ranges: GGT normal values are 0-50 U/L for adults and children, with some labs using 15-40 U/L (NHS UK guidelines). Medical News Today +2 Males typically have slightly higher baseline levels than females. clevelandclinic What Elevated GGT Indicates: GGT greater than 500 U/L indicates severe liver damage or significant bile duct obstruction. GGT is the most sensitive marker for bile duct problems and typically the first liver enzyme to rise with biliary issues. Testing.com This extreme elevation suggests critical hepatocellular injury or cholestatic disease requiring immediate medical evaluation. Clinical Significance by Level: Normal (0-50 U/L), Medical News Today mild elevation (51-100 U/L), moderate elevation (101-300 U/L), severe elevation ( greater than 300 U/L), and critical elevation ( greater than 500 U/L) requiring urgent assessment. Levels greater than 1000 U/L combined with other liver enzyme elevations strongly suggest acute liver failure. Most Common Causes: Bile duct obstruction from gallstones or tumors, alcoholic liver disease (75% of chronic drinkers show elevated GGT), non-alcoholic fatty liver disease, viral or drug-induced hepatitis, Testing.com primary biliary cholangitis, and medications like phenytoin or phenobarbital. American Academy of Family Physicians Alcoholic liver disease shows the strongest correlation with markedly elevated GGT levels. Critical Warning Signs: GGT greater than 1000 U/L with elevated ALT/AST suggests acute liver failure. Immediate medical attention required when combined with jaundice, severe abdominal pain, mental confusion, or signs of bleeding. These combinations indicate potential life-threatening liver dysfunction requiring emergency intervention.