Thank you for asking your query at DoctorSpring.
Low TSH with normal T3 and T4 with no symptoms is likely to be due to Inflammation of thyroid (thyroiditis), or early hyperthyroidism. This can be differentiated by a thyroid scan. Thyroid antibodies test will also help. Alternatively you can repeat the test after a month or two. There is no reason to worry though, as these conditions are not dangerous or cause of concern.
PS : If you are you on thyroxine treatment already for hyperthyroidism, then this pattern of test result can also mean overdose.
Hope this helps
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