Thyroid function test for the diagnosis of hypothyroidism or hyperthyroidism, used with thyroxine (T₄) or equivalent to provide free T₄ index, FTI. An indirect measure of binding protein, the T₃uptake reflects available binding sites (ie, reflects TBG). T₃ uptake is not a measurement of serum T₃. It should never be used alone; rather, its usual application is use with thyroxine (T₄).

After placing an order, you will receive a doctor approved lab order by email usually within 20-30 minutes. The emailed Lab Requisition will allow you to go to a local patient collection site to get tested. You will not have to pay any additional lab, collection or doctor's fees.  Most test will normally report within 48-72 hours by secure email. List of collections site can be found using our Lab Locator Tool. If you have any questions please call our offices at 1-844-455-6355 or chat online with a member of our Care Team.