resizedimage150150 ThyriodAn appropriate health professional or medical doctor should always be consulted if a serious condition is suspected. All the information here should not be considered as conclusive medical advice.

Related test item

 (Thyroid StimulatingHormone)
Produced by the pituitary gland to regulate the amount of T3 and T4 levels in the body.
Free T4

The T4 Concentration has been used to help diagnose hyperthyroidism and hypothyroidism. It is a useful test but can be affected by the amount
of protein available in the blood to bind to the hormone.

The free T4 test is a newer test that is not affected by protein levels. Since free T4 is the active form of thyroxine, the free T4

test is thought to be a more accurate reflection of thyroid hormone function. It is usually ordered along with or following a TSH test.

 Free T3 Free T3 measures the amount of T3 that is not bound to proteins and that which is useable.