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At a Glance
Why Get Tested?
When to Get Tested?
For screening: Newborn screening is widely recommended; however, there is no consensus within the medical community as to the age adult screening should begin or whether screening should be done.
For monitoring treatment: as directed by your healthcare provider
Otherwise: when a person has symptoms of hyperthyroidism or hypothyroidism and/or an enlarged thyroid
A blood sample drawn from a vein in your arm or from pricking the heel of an infant
Test Preparation Needed?
None needed; however, certain medications can interfere with the TSH test, so tell your health practitioner about any drugs that you are taking. If you take thyroid hormone as treatment for thyroid disease, it is recommended that your blood sample be drawn before you take your dose for that day.