The thyroid is a butterfly-shaped gland that is responsible for producing two hormones that are important for the body’s well-being, such as thyroxine (T4) and triiodothyronine (T3). However, for the thyroid to effectively produce these substances it must be stimulated by another hormone known as Thyroid Stimulating Hormone (TSH).
TSH, as its name implies, is the substance in charge of stimulating the thyroid to produce T3 and T4, substances that help regulate the metabolism and the functioning of many organs, and when they are scarce they can produce important disorders in the body. human. If your doctor recently asked you to check your TSH levels, don’t worry, this is a routine test to determine the function of your thyroid gland. We invite you to continue reading this FastlyHealarticle to learn what TSH is in a blood test.
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TSH in a blood test
The TSH in blood is the test that is carried out to know the levels of this hormone in the body fluid of a person. This test will determine if the amount of thyroid stimulating hormone (TSH) produced by the pituitary gland is sufficient for the thyroid gland to work properly. This test is usually done in conjunction with the T3 and T4 test to find out the amount of thyroid hormones the gland is secreting.
Unlike when measuring cholesterol or sugar, it is not necessary to fast or any type of preparation to carry out this analysis. However, it is important to talk to our doctor and mention the medications we are taking to see if any of them may interfere with the result of the analysis. Generally, people should stop taking the following drugs before a TSH test:
- Potassium iodine.
- Prednisone or glucocorticoids.
Medical specialists, specifically endocrinologists, often ask for blood TSH measurement when they suspect that a person may be having a disease related to the thyroid gland such as hyperthyroidism or hypothyroidism . People who suffer from any of these conditions also often have this test to assess the progress and control of their disease.
Normal TSH values in a blood test
TSH is a test that is ordered to analyze the function of the thyroid gland and its ability to produce the hormones T3 and T4. The normal values of this hormone in the blood range between 0.4 and 4.0 mlU / L (international milliunits per liter). However, it is important to note that the values of this hormone produced by the pituitary can vary throughout the day, which is why it is recommended to carry out this test first thing in the morning. There are doctors who consider that a TSH value above 2.5 implies a malfunction of the thyroid gland.
Depending on the laboratory where the test is performed, different ranges of values can be found. When a person is being treated for any thyroid-related condition, TSH will remain between 0.4 and 4.0, unless:
- There is a problem with the functioning of the pituitary gland and the TSH levels are lower than expected.
- The person has had thyroid cancer in the past.
- It is a pregnant woman. The range of hormonal values changes during the gestation process.
Abnormal TSH results in a blood test
When this test has not been successful and the TSH values are above the established range, it is considered that the person has an underactive thyroid gland , that is, that the person suffers from hypothyroidism or does not consume the appropriate treatment to treat this condition .
However, when the levels are below normal, the gland is considered to be overactive and the individual suffers from hyperthyroidism or the amount of thyroid hormone consumed to treat this disease is excessive.
It is very uncommon for a TSH test with very low levels to be associated with a malfunction of the pituitary gland, usually the abnormal values of this test show a hormonal disorder in the thyroid gland or the poor treatment of pre-existing conditions. Although the test shows that there are problems with the activity of the gland, it is not enough to discover the reason. Therefore, a person with an abnormal TSH result may need further tests to discover the cause of the disorder.
This article is merely informative, at FastlyHeal .com we do not have the power to prescribe medical treatments or make any type of diagnosis. We invite you to see a doctor in the case of presenting any type of condition or discomfort.
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I am a Surgeon with a diploma in comprehensive ultrasound and surgical care residency, an area I am specializing in. During the exercise of my profession, I have realized the need for patients to know the diseases they suffer, and I can tell you that a large part of their complications is due to a lack of information. Being a health web writer allows me to transmit my experience, without borders, to all those readers eager for knowledge, educate them in the prevention of diseases and promote a healthy lifestyle.