What is this test?
Thyroid Function Test panel measures the levels of total thyroxine T-4, total triiodothyronine T-3 and thyroid stimulating hormone (TSH) in blood.
What is Thyroid Stimulating Hormone?
The thyroid stimulating hormone is a pituitary hormone that stimulates the thyroid gland to produce triiodothyronine (T3) and thyroxine (T4) hormones. These hormones help to control the rate at which energy is used in almost every tissue in the body.
What are T4 and T3 Hormones?
Thyroxine (T4) and Triiodothyronine (T3) which are secreted into the blood binds reversibly to the transport proteins like thyroxine-binding globulin (TBG), thyroxine binding prealbumin (TBPA), and albumin. Remaining unbound T4 and T3 circulates freely in blood and used by the body. This freely circulating Thyroxine (T4) and Triiodothyronine (T3) are known as Free Thyroxine FT-4 and Free triiodothyronine FT-3.
What are Hyper and Hypothyroidism?
This test is performed to measure whether the thyroid gland is hyperactive (Hyperthyroidism) or underactive (Hypothyroidism). Hyperthyroidism is a condition in which thyroid gland produces excessive hormones. This condition may cause signs and symptoms such as weight loss, irritability, sweating, and irregular heartbeats. Hypothyroidism is a condition in which thyroid gland does not produce enough hormones. This condition may cause weight gain, dry skin, constipation, feeling cold and slow heart rate. Your doctor may ask you to undergo this test if you exhibit any of these signs or symptoms. mane
Why This Test is Done?
The doctor may ask to get this test done if the patient is suffering from symptoms like unexplained weight loss or weight gain, fatigue, weakness, difficulty in concentrating which are common symptoms of thyroid disorders. In some cases, this test is performed to find out the effectiveness of the treatment. If a patient is on the treatment of artificial thyroid hormones then the doctor prefers this test to evaluate and to check the thyroid hormone levels in the body. This helps the doctor to rule out the patient’s disease condition.