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Why Get Tested?
To help evaluate thyroid gland function; to help diagnose thyroid disease; to screen for hypothyroidism in newborns; to monitor effectiveness of treatment
When to Get Tested?
When having signs and symptoms of thyroid disease, after an abnormal TSH test; when you are being treated for a thyroid disorder
Sample Required?
A blood sample drawn from a vein in your arm or from pricking the heel of an infant
Test Preparation Needed? Usually none; however certain thyroid medicines can interfere with Free T4 result.