Why is it important to maintain T3 within the normal range?

The origin of the T3 gland is the thyroid gland. The gland is located in the throat. It is positioned below Adam’s apple. The gland is responsible for producing hormones which would control how the body would be dealing with energy. It also decides how sensitive the body would be to the other hormones. Among the hormones that are produced by the thyroid, one if known as triiodothyronine. It is also called T3. The T4 hormone – thyroxine is also produced by the thyroid. These hormones are together responsible for regulating the heart rate, metabolism and the temperature of the body. Most of the T3 hormone binds to proteins. The hormone that does not do so circulates in the blood and is known as free T3. The common T3 test, which is termed as the T3 total test, would measure both these T3 types in the blood. The T3 normal range should prevail for the proper functioning of the different organ systems in the body.

Why would the doctor ask you to perform the T3 test? 

The doctors generally instruct to perform the T3 test if there is a problem with the thyroid. The potential problems include:

• hypopituitarism – when the pituitary gland – the master gland is not producing enough hormones to keep the thyroid working at normal levels
• hyperthyroidism – when the thyroid is secreting too much of hormone
• primary or secondary hypothyroidism – when the thyroid is producing less than normal amounts of the hormone
• thyrotoxic periodic analysis – when the thyroid is producing high levels of hormones, which results in the muscles becoming weak

Thus the T3 test is primarily used to find out if there is any problem going on with the thyroid. It is quite similar to the LDH test, which is also used to find out if there are any problems related to the organs where the enzyme can be located.

The thyroid disorder would generally cause a wide range of symptoms and can be quite easily identified. There might be issues like anxiety and physical problems like menstrual irregularity and constipation. The person would also be facing problems like difficulty in sleeping, fatigue and weakness, loss or gain of weight, a dry or puffy skin, an increased sensitivity to heat or cold, loss of hair, puffy or bulging eyes, increased heart rate and hand tremors. If the thyroid problem can be confirmed, the doctor would use the test to verify the changes in the condition. The TSH test or T4 hormone can also be ordered by the doctor depending on what he wants to find out.

What are the preparations needed for the test? 

The doctor must be informed about the medications currently being taken. The doctor might ask you to stop the medications temporarily so that the correct results can be seen. The medications that affect the T3 levels are steroids, birth control pills and drugs related to thyroid. A sample of blood is drawn and tested in the laboratory. The clotting time test can also be ordered depending on the situation.

What to expect with the results? 

The normal results should indicate the levels between 100 to 200 ng/dL. The normal result would mean that the thyroid is working properly. Measuring the levels can help the doctor to figure out if there is any problem with your thyroid.

The single test might not give enough answers to the doctor. But abnormal results can point out that there is a problem with the thyroid. The elevated levels might indicate that there is some issue with the thyroid like hyperthyroidism, Graves’ disease, a toxic nodular goitre, painless thyroiditis or thyrotoxic periodic paralysis. The abnormally low levels might indicate hypothyroidism or starvation.

Thus a T3 test is all that is needed to find out if there is any problem going on with the thyroid.

https://www.healthline.com/health/t3#abnormal-results