Hi i am hyperthyroid and use to take 350mcg utroxin.i left taking mediine since 3years.now i went for normal chekup and my tsh was516. what to do?

See endocrinologist: Your TSH level of 516 is remarkably elevated, strongly suggesting hypothyroidism and a requirement now to take supplemental thyroxine. It is not uncommon after ablative treatment of hyperthyroidism to overshoot the goal of "normal", and end up hypothyroid needing replacement therapy.

Hyperthyroid???: Are u certain u were being treated for overactive thyroid? Eltroxin is used for underactive thyroid. As pointed out, TSH of 516 is very high, indicating very low thyroid activity. Need to see pcp/endocrinologist for thyroid hormone replacement.