Thyroid Function Test- For measuring how well the thyroid gland is working
Thyroid function tests (TFTs) is a collective term for blood tests used to check the function of the thyroid.
TFTs may be requested if a patient is thought to suffer from hyperthyroidism (overactive thyroid) or hypothyroidism (underactive thyroid) or to monitor the effectiveness of either thyroid-suppression or hormone replacement therapy. It is also requested routinely in conditions linked to thyroid diseases, such as atrial fibrillation and anxiety disorder.
Thyroid-stimulating hormone (TSH, thyrotropin) is generally increased in hypothyroidism and decreased in hyperthyroidism, making it the most important test for early detection of both of these conditions. The result of this assay is suggestive of the presence and cause of thyroid disease, since measurement of elevated TSH generally indicates hypothyroidism, while a measurement of low TSH generally indicates hyperthyroidism. However, when TSH is measured by itself, it can yield misleading results, so additional thyroid function tests must be compared with the result of this test for an accurate diagnosis.