Archive

Free T4 measures the unbound, active form of the T4 hormone circulating in your blood. It's considered a reliable and direct indicator of thyroid gland activity and is commonly used to diagnose and monitor thyroid disorders.

Free T3 measures the unbound, active form of the T3 hormone that's available for the body to use. It's considered a more accurate measure of thyroid function than total T3, since it isn't affected by protein levels in the blood.