By measuring levels of thyroid hormones in the blood, the thyroid panel can help diagnose

thyroid disorders and disrupted thyroid function. A thyroid panel can also be used to

monitor the treatment of hyperthyroidism and assess patients receiving levothyroxine therapy.

This test measures the level of triiodothyronine (T3) in your blood. T3 is one of two

major hormones made by your thyroid, a small, butterfly-shaped gland located near the

throat. The other hormone is called thyroxine (T4.) T3 and T4 work together to regulate

how your body uses energy.