Free T3 (Free Tri-iodothyronine)

A Free T3 Blood Test is used to evaluate thyroid function. Tri-iodothyronine (Free T3) normally is almost entirely bound to proteins in the Blood, with only 0.25% of the total being in the free state. Measurement of Free T3 is of value in confirming the diagnosis of hyperthyroidism, when an elevated free or total thyroxine level is found. Abnormal total and free tri-iodothyronine (Free T3) concentrations may appear in T3 toxicosis, in the presence of normal thyroxine levels.

Often, a thyroid panel with Thyroid Stimulating Hormone (TSH) is first performed before free T3 is measured.

You may order this Free T3 Blood Test online, or for more information call LabSafe toll free at 1-888-333-LABS to speak with one of our medical counselors.