Thyroid TSH w/ Free T4 & Free T3

FAQ

1. What is the difference between T3, T4, and TSH in thyroid testing?

   The thyroid produces T3 and T4 hormones; the pituitary gland produces Thyroid-stimulating hormone (TSH). TSH stimulates the production of these two hormones (T3 and T4). T4 is the main circulating form of thyroid hormone and acts as a source of nourishment for the cells. Healthy kidneys, liver, gastrointestinal tract, and other organs will help convert T4 into T3, which is the active form. Together, they help determine if an individual has:

   • Normal functioning thyroid
   • Hypothyroidism
   • Hyperthyroidism
   • Pituitary disorders

2. How accurate is TSH when testing the thyroid?

   TSH is very accurate in testing the thyroid. If a person has low or high levels of TSH, then they likely have hypo or hyperthyroidism, respectively. The pituitary gland regulates TSH production, so if there is a problem with your thyroid gland, TSH production will be abnormal.

3. What does the TSH thyroid blood test tell you?

   TSH is the hormone that travels through the bloodstream and gives orders to the thyroid, which produces T3 and T4 in accordance. TSH levels provide insight into what your thyroid hormone levels are:

   • If you have a high TSH, your pituitary gland tells your thyroid to produce more hormones.
   • If you have a low TSH, it can mean your body isn't using its available hormones effectively, possibly because you don't have enough in circulation or your thyroid isn't responding efficiently to the pituitary gland.

   If any of these are your case, speak to your doctor to explore treatment options.

4. Do I need to visit a doctor?

   No doctor visit needed.

5. How do I get my results?

   You get your results via email as soon as they are available.

6. Does my lab prescription expire?

   Your lab prescription never expires.*