In primary hypothyroidism, thyroid-stimulating hormone (TSH) levels are elevated. In primary hyperthyroidism, TSH levels are low. Elevated or low TSH in the context of normal free thyroxine is often referred to as subclinical hypo- or hyperthyroidism, respectively. In hyperthyroidism, both thyroxine (tetraiodothyronine; thyroxine: T4) and T3 levels (total and free) are usually elevated, but in a small subset of hyperthyroid patients (T3 toxicosis) only T3 is elevated. Free thyroxine (fT4) comprises a small fraction of total thyroxine. The fT4 is avaialable to the tissues and is, therefore, the metabolically active fraction. Elevations in fT4 cause hyperthyroidism, while decrease causes hypothyroidism. Disorders of the thyroid gland are frequently caused by autoimmune mechanisms with the production of autoantibodies known as anti-TPO antibodies.
Digital Results Available Within
3-5 days of the lab receiving the sample
TSH, fT3, fT4, TPO
How It Works
Step 1: Order Test Kits
Use the form above to order kits and your test kits will be delivered promptly.
Step 2: Register Your Test Kit
When your test kit arrives, follow the simple instructions to ensure your test is registered with your personal information.
Step 3: Collect Your Sample
Everything you need is included, and collection takes only a few minutes. Use the shipping return mailer to send your sample to the lab.
Step 4: Receive Your Results
Once the lab receives your sample, you will get your test results and recommendations within 5 days.