Several direct and indirect mechanisms have been suggested as the cause of liver dysfunction in hyperthyroidism. Summarily, these include direct liver toxicity from prolonged exposure to excessive thyroid hormones and hepatocyte anoxia with free-radical damage as a result of the hypermetabolic state, liver cell degeneration from accelerated liver glycogen and protein decomposition, autoimmune-related liver injury, congestive hepatopathy (necrosis) from concomitant thyrotoxic heart failure, previous underlying liver disease and antithyroid medication-related liver toxicity and injury,
..... Rises in ALP and GGT are seen about 64% and up to 62% of thyrotoxicosis cases respectively.