Brief Answer: Hi and welcome to XXXXXXX Detailed Answer: Thanks for the query. GGT is used mainly for detecting liver diseases including excessive alcohol intake,but it may indicate any other liver disease,hepatitis,gallbladder issue as well as cardiovascular diseases. Also some drugs can cause liver enzymes elevation(including amytriptiline). If your other LFTs are fine and you odnt have any liver related symptoms, then isolated GGt elevation isnt worrying and you should just avoid alcohol and fatty food in next 3-4 weeks and repeat blood test then. You should do just liver ultrasound to rule out some morphologic liver changes. Your hypthyroidims problem probably isnt related to ggt levels. It is not uncommon that hypo- becomes hyperthyroidms or conversely. There can be thyroid tissue that became hyperfunctional. usually this is just thyroid hyperplasia or adenoma,but sometimes it can be something more serious such as tumors. So I would sugest to do thyroid ultrasound or scintigraphy to see the exact cause of high T4 and determine is medical therapy necessary. Wish you good health. Feel free to ask. Regards

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