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Gamma-Glutamyl Transferase, Gamma-Glutamyl Transpeptidase, GGTP, Gamma-GT, GTP


Gamma-glutamyl transferase (GGT) is an enzyme (protein) found in the liver and bile ducts.

A high GGT level in the blood indicates a liver impairment, but it does not specify which type (hepatitis, cirrhosis, bile duct disease, etc.). Generally speaking, the more severe the liver impairment, the higher the GGT levels. Other conditions can also cause high GGT levels, such as congestive heart failure, diabetes, pancreatitis, alcoholism, as well as the ingestion of a number of drugs.

A low or normal GGT level indicates that liver impairment is very unlikely or that the person has not consumed any alcohol recently. Drinking even small amounts of alcohol can raise GGT levels, which is why this test is often used to monitor alcoholism.

If combined with a high alkaline phosphatase level, a high GGT level indicates liver impairment, while a normal GGT level generally indicates that the high alkaline phosphatase level is more likely due to bone disease.

Medications that can raise GGT levels include DilantinTM, carbamazepine and phenobarbital, nonsteroidal anti-inflammatory drugs (NSAIDs), cholesterol medications, and so on.

Term of the Week

Hot zone

A hot zone is a section of a facility (sometimes an entire facility or even a city district) where there is a high risk of contamination by patients with an infectious disease. All individuals entering a hot zone must respect appropriate protective measures. By analogy, “cold zone” and “warm zone” are used to refer to areas where there is no infected individual or only individuals suspected of having an infection.