The thyroid gland is responsible for multiple functions of the body. When the functions are interrupted, various ailments can be experienced. Thyroid function test helps in identifying the problems with the thyroid gland. The underactive thyroid, also known as, hypothyroidism, and overactive thyroid, also known as hyperthyroidism can be determined using this thyroid test. This is a blood test, which checks the level of thyroid hormone made by the pituitary gland.
About Thyroid Function Test
This is a simple blood test. The laboratory technician draws some blood from your veins and analyses the sample. The test result will not take more than a couple of days. You do not need to get ready in any way for the test and generally, no fasting is required. You can just walk in or ask someone to visit and collect the blood samples. But, if you are under medication, inform your doctor about the same as thyroid function test done after taking thyroid pills might affect the test results. If you have undergone X-ray again, tell your doctor. The medicines can influence the results, and iodine in X-rays that use contrast dye too can manipulate the readings.
The thyroxine and the Thyroid Stimulating Hormone, TSH, work together and maintain a balance for proper functioning. To ensure the thyroid gland is working correctly, the TSH is produced by the brain in the right amount. The gland has to produce the exact amount of hormone required, not more or not less. This is what happens in a person with healthy hormones. When more thyroxine is produced, the brain gets the signal to produce less TSH and vice versa. This feedback loop helps in maintaining healthy thyroid levels. One of the most important things to be kept in mind when it comes to thyroid blood test is the fact that the thyroid levels do not change overnight. It takes weeks or even months for some changes to take place. So, whenever your tests indicate that the functioning of the thyroid gland is not right, then your doctor will ask you to undergo this multiple times for a period of 3 to 6 months. This is to ensure the proper results are shown in the test that reflects the right condition of your health.
When your thyroid levels are healthy, you can see numbers like:
0.4 to 4.0 mU/ml for the Thyroid Stimulating Hormone (TSH)
9.24 pmol/L for thyroxine When the TSH is low, and thyroxine is high, you will have an overactive thyroid, and if TSH is high, and thyroxine level is low, then you have an underactive thyroid. Subclinical hyperthyroidism is a condition where the TSH is high, but the thyroxine is normal.
You might have a high risk of thyroid problems when you suffer from Type 1 diabetes, Addison’s disease, and coeliac disease. People with Down Syndrome and Turner Syndrome, too are required to take the test once a year. Medications that involve consuming lithium and amiodarone can also lead to improper functioning of the thyroid gland.
You do not need to worry about spending time in the laboratory for the test to be done. Many diagnostic centers offer thyroid test at home, and you can give your samples at the comfort of your home, and know the results in two days.