A Thyroid-Stimulating Hormone test is used to figure out any problem in the thyroid gland and the amount of thyroid stimulating hormone in the blood. TSH is made by the pituitary gland.
A blood sample is required to complete this test, and no preparation is necessary prior the test. However, there are some medications that a person may be required to stop before the test, including lithium, amiodarone, potassium iodide, dopamine and prednisone, as stated by MedlinePlus. The test is carried out to identify any symptoms and the cause of an underactive or overactive thyroid gland. Radioactive materials may affect the results of the test, as stated by WebMD.