Free Thyroxine (FT4)

A FT4 Test is designed to directly reflect the equilibrium existing in serum between T4 and TGB-bound T4. The free thyroxine is a measure of the amount of T4 in relation to the amount of thyroxine-binding globulin present. The FTI is calculated from the T4 and T3U values. The FTI value can indicate when an abnormal level of T4 is due to an abnormal level of thyroxin-binding globulin in the blood. Generally, a Thyroxine Free Blood Test is run with other thyroid tests so that it is meaningful (see Thyroid Panel test).

Call LabSafe toll free at 1-888-333-LABS to speak with a Medical Counselor for further information on a FT4 Test, or simply place your order for a Thyroxine Free Blood Test online.