Free T4 Thyroxine Normal. When they find that their tsh is abnormal the lab company will automatically order free t4. What is the role of t4 (thyroxine)?
Free thyroxine (free t4) optimal range: Levothyroxine therapy and serum free thyroxine. Fluctuations in protein levels do not affect free t4, so free t4 is a more reliable measurement of t4 levels in the blood.
At your next visit with your doctor you may discuss getting free t4 and t3 ( liothyronine ) done for confirmation of normal status.
T4 tests t4 is the main form of thyroid hormone circulating in the blood. Fluctuations in protein levels do not affect free t4, so free t4 is a more reliable measurement of t4 levels in the blood. Pregnant women have normal values above the ranges before. Free thyroxine is often more useful than total thyroxine in assessing thyroid function.