Book Thyroid Stimulating Hormones - TSH Test

TEST CODE: HTTBIO0493

LOINC: 3016-3

TEST NAME: TSH

TEST DESCRIPTION

The thyroid gland is butterfly-shaped and is located in the neck below the Adam's apple. It regulates various physical functions in the body, including metabolism, energy levels, and mood swings. The TSH test measures the level of TSH in your body, which is a hormone produced by the pituitary gland in your brain. This test can help evaluate the functioning of the thyroid gland and guide further diagnostic testing and treatment decisions.

Thyroid tests can help diagnose:

Hypothyroidism

Hyperthyroidism

Thyroiditis

SYMPTOMS

Hypothyroidism

Weight gain or loss

Brittle nails

Fatigue 

Depression.

Hyperthyroidism

Weight loss or gain,

Elevated mood

Anxiety

Diarrhea

Thyroiditis

Neck pain

Weight fluctuations

Fatigue

Heart rate changes

Hair loss.

STEPS TO FOLLOW BEFORE TESTS

Typically, you don't need to do anything special before the test. However, some healthcare providers may recommend fasting for a few hours before the test to ensure accurate results.

NORMAL RANGES

^*Reference range may vary depending on equipment used by labs. Consult your referring doctor for proper interpretation of test results.

SOME SAFETY ADVICE TO FOLLOW

Learn about thyroid problems: Talk to your doctor about what causes thyroid problems and how they affect your body. There are many resources available online and in libraries that can help you learn more about thyroid problems.

Track your symptoms: Keep a journal of your symptoms so you can track how they change over time. 

Share your medications and supplements with your doctor: Make sure your doctor knows about all the medications and supplements you are taking, including over-the-counter medications and herbal remedies. Some medications and supplements can interact with thyroid medications, so it's important to let your doctor know about everything you're taking.

Get regular blood tests: Your doctor will likely recommend getting regular blood tests to check your thyroid levels. This will help them monitor your condition and adjust your treatment as needed.

Eat a healthy diet: Eating a healthy diet can help support thyroid function. Include foods that are rich in iodine, such as seaweed and fish, and selenium, such as nuts and eggs.

SOME USEFUL INFORMATION

A thyroid test is essential for assessing the health of the thyroid gland and detecting thyroid disorders. 

Here are the reasons why a doctor may suggest getting a thyroid test:

Detecting Hypothyroidism: A thyroid blood test, particularly measuring TSH levels, helps identify hypothyroidism, a condition where the thyroid gland produces insufficient thyroid hormones.

Subclinical Hypothyroidism: If TSH levels are between 5.00 and 9.99 mIU/L, it may indicate subclinical hypothyroidism. Further testing, such as a T4 test, can determine whether thyroid hormone replacement therapy is necessary.

Unawareness of Thyroid Issues: Regular thyroid tests are crucial because people with hypothyroidism or subclinical hypothyroidism may be unaware of their condition without proper testing. 

Tailored Treatment: Synthetic thyroid hormone replacement therapy is an effective way to manage hypothyroidism. Treating the condition reduces the risk of severe health issues like cardiovascular disease.

How thyroid blood tests work: Thyroid blood tests analyze specific hormones in the blood to assess thyroid function and detect thyroid diseases. Some examples of thyroid blood tests include:

TSH Test: Measures the level of thyroid-stimulating hormone (TSH) produced by the pituitary gland in the brain. 

T3 Test: Measures the amount of triiodothyronine hormone (T3) in the blood. T3 is one of the main hormones produced by the thyroid gland and plays a crucial role in regulating metabolism.

T4 Test: Measures the amount of thyroxine hormone (T4) in the blood. T4 is another primary hormone produced by the thyroid gland and serves as a precursor to T3.

ALIASES (Other names that describe the test. Synonyms.) B12 Assay

Thyrotropin

TSH

TSH, Pregnancy

ORDERING RECOMMENDATION

Preferred test for initial screening and monitoring of thyroid function.

FREQUENTLY ASKED QUESTIONS

[QUESTION] What is the TSH test, and why is it important?

[ANSWER] The TSH test measures the level of thyroid-stimulating hormone in the blood. It is essential because TSH plays a crucial role in regulating thyroid function, and abnormal levels can indicate thyroid disorders.

[QUESTION] How TSH test is performed?

[ANSWER] The TSH test involves a simple blood draw from a vein in the arm. The blood sample is then sent to a laboratory for analysis.

[QUESTION] What are normal TSH levels?

[ANSWER] Normal TSH levels typically fall within the range of 0.27 to 5.3 micro–International Units per milliliter (µIU/mL). However, the specific reference range may vary depending on the laboratory.

[QUESTION] What do abnormal TSH levels indicate?

[ANSWER] Abnormal TSH levels can indicate thyroid dysfunction. High TSH levels may suggest an underactive thyroid (hypothyroidism), while low TSH levels may indicate an overactive thyroid (hyperthyroidism).

[QUESTION] What are the symptoms of thyroid disorders?

[ANSWER] Thyroid disorders can cause a wide range of symptoms, including fatigue, weight changes, hair loss, mood swings, and changes in heart rate. However, symptoms alone are not enough to diagnose a thyroid disorder accurately.

[QUESTION] When should I consider getting a TSH test?

[ANSWER] You should consider getting a TSH test if you experience symptoms of thyroid dysfunction, such as unexplained weight changes, persistent fatigue, or changes in your hair and skin.

[QUESTION] Can stress affect TSH levels?

[ANSWER] Yes, stress can potentially influence TSH levels. High stress levels and the release of stress hormones can disrupt the normal functioning of the hypothalamus-pituitary-thyroid axis, affecting TSH production.

[QUESTION] Can pregnancy affect TSH levels?

[ANSWER] Yes, pregnancy can impact TSH levels. During the first trimester, TSH levels often decrease slightly. Regular monitoring of thyroid function is essential during pregnancy to ensure a healthy pregnancy outcome.

[QUESTION] How often should TSH levels be checked?

[ANSWER] The frequency of TSH testing depends on individual factors and your healthcare provider's recommendations. Generally, individuals with known thyroid conditions may require more frequent monitoring.

[QUESTION] Are there any factors that can interfere with TSH test results?

[ANSWER] Certain medications, supplements, and underlying medical conditions can affect TSH levels. It is crucial to inform your healthcare provider about any medications or health conditions before undergoing the test.

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