All You Need to Know About Thyroid Function Test

The thyroid gland is located in the lower part of the neck. It wraps around the windpipe (trachea) and is shaped similar to a butterfly. The two wing-like structures called lobes and attached by a middle part known as the isthmus. It is responsible for regulating various functions of the body including metabolism, energy generation, and temperament.

Functions of the Thyroid Gland

The thyroid gland produces hormones that are essential for the body’ metabolism. The tests involved in thyroid function test can help in evaluating whether the thyroid gland hormone production is normal, overactive, or underactive. The thyroid gland uses iodine (usually found in foods like seafood, bread, and salt) to produce thyroid hormones. The gland produces two major hormones namely, triiodothyronine (T3) and thyroxine (T4). A thyroid function test is a series of blood tests including T3, T3RU, T4, and TSH. One can easily book an appointment for the prescribed thyroid test online.

Symptoms

If the thyroid gland is unable to produce a normal level of hormones, the individual may experience symptoms such as:

· Fatigue

· Increased sensitivity to cold

· Constipation

· Dry skin

· Weight gain

· Puffy face

· Hoarseness

· Muscle weakness

People with these symptoms might have to undergo broad screening tests, such as the T4 or the thyroid-stimulating hormone (TSH) test.

Types of Thyroid Tests

· T4 and TSH Tests

The T4 test and the TSH test are the two most common thyroid function tests and are usually prescribed together. This test is known as the thyroxine test. T4 and TSH tests are commonly carried out on new-born babies regularly to identify a low-functioning thyroid gland. If left untreated, this condition can lead to developmental disabilities.

High levels of T4 indicates an overactive thyroid, a condition known as hyperthyroidism. On the other hand, the TSH test measures the level of thyroid-stimulating hormone in the blood. The normal test range of TSH is between 0.4 and 4.0 milli-international units of hormone per litre of blood (mIU/L). If the results of these tests indicate an abnormality in the levels of the hormone, the individual might have to get further tests to identify the underlying cause of this issue.

· T3 Test

The T3 test checks for levels of the hormone triiodothyronine and is usually done if T4 tests and TSH tests suggest hyperthyroidism. It can also be prescribed if the individual is showing signs of an overactive thyroid gland.

· T3 Resin Uptake Test

A T3 resin uptake is a blood test that measures the binding capacity of a hormone called thyroxin-binding globulin (TBG). Also known as a T3RU, if the results of this test show low levels of T3, it may indicate a problem with the kidneys.

Thyroid function tests can help in keeping a tab on one’s thyroid gland, its activity, and any underlying causes that can ensure proper management and treatment of a certain disorder. Thus, it is advised that one should get these tests from only the best diagnostic centre near them.