TSH or Thyroid Stimulating Hormone test is used to screen for and diagnose thyroid disorders; to monitor treatment of hypothyroidism and hyperthyroidism.
This test should not be used in isolation. There are other tests in the Advanced Thyroid function panel that need to be assessed in conjunction with TSH.
TSH is the “messenger” sent by the pituitary gland in the brain to the thyroid to start working. When the thyroid is producing too much of hormones, the TSH is down to convey the message to the thyroid to slow down.
Low levels of TSH mean that the thyroid gland is overproducing hormones. For people who take thyroid hormone supplementation, it may also indicate that they take too much of it. Please, never stop your medications before consulting your health professional.
High levels of TSH mean that the thyroid gland is slow in producing its own hormones. Very rarely, increased TSH may indicate the problem with the pituitary gland itself.