Description
Gamma glutamyl transferase (GGT) is a liver enzyme whose levels may be elevated in conditions involving liver damage. GGT levels are useful in the evaluation of obstructive liver disease, since they are more organ-specific than alkaline phosphatase (ALP). They are also elevated in chronic alcoholics,when other tests are normal, and during antiepileptic therapy. Disproportionate elevation of both ALP and GGT indicates drug-induced cholestasis.