All Tests, General Health, Hormones
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Free T3 Test

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$ 89.0
$89

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Learn more about your thyroid function with a free T3 test.

A free T3 test measures the level of free triiodothyronine (T3) in your blood. T3 is a hormone produced by the thyroid gland that regulates metabolism, energy levels, and other bodily functions. This test measures the level of T3 hormone in the blood that is not bound to proteins, providing a partial assessment of thyroid function. This test helps evaluate whether the thyroid is producing the right amount of T3, which is essential for regulating metabolism and energy levels.

 

Testing free T3 level can help you and your healthcare provider evaluate symptoms and conditions that may be related to a free T3 level. Free T3 is often evaluated in the context of other thyroid function tests such as thyroid-stimulating hormone (TSH) and free T4 to gain a full picture of your thyroid health.

 

Free T3 Test
$ 89.0
$89

Test Details

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Sample Type: Blood
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Collection Method: In person at a Labcorp location
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Age: 18+
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Results: Within 1-2 days from when your sample arrives at our lab
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HSA/FSA: Accepted
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Test must be taken by purchaser

Preparation: If you’re taking a supplement containing biotin (also called vitamin B7 or B8, vitamin H, or coenzyme R), commonly found in products promoting nail, skin and hair health, it is recommended that you wait at least 72 hours from your last dose before sample collection.

What's Tested
  • Free T3

    Free T3, or triiodothyronine, is a hormone produced by the thyroid gland that plays a crucial role in regulating metabolism, heart function and overall energy levels. This test measures the amount of free T3 in the blood, which is the active form not bound to proteins. A free T3 level helps assess thyroid function and evaluate conditions such as hyperthyroidism (too much thyroid hormone) or pituitary disorders. Elevated free T3 levels may indicate an overactive thyroid, which can lead to symptoms such as irregular heartbeat, weight loss, anxiety and fatigue.

FAQ

  • The T3 free test measures the level of free T3 in the blood to evaluate thyroid function. Free T3 is the active form of the hormone that is not bound to proteins and can directly influence the body's processes. Understanding free T3 levels can help assess thyroid function. Abnormal T3 levels are often associated with conditions such as hyperthyroidism or pituitary disorders.
     

    By measuring free T3 levels alongside other thyroid hormones like TSH and free T4, you and your healthcare provider can get a more complete picture of your thyroid health.

  • Elevated free T3 levels may indicate hyperthyroidism. You may need a free T3 test if you have symptoms.1 Symptoms may include:
     

    • Anxiety, nervousness, irritability
    • Weight loss, even though your appetite may increase
    • Shaky hands, muscle weakness
    • Sweating or being very sensitive to heat
    • Irregular heartbeat (arrhythmia)
    • Frequent bowel movements (poops)
    • Goiter (an enlarged thyroid gland)
    • Trouble sleeping and fatigue
  • The normal range for free T3 levels may vary depending on the laboratory that performs the test, as well as age and sex. Your test results will include Labcorp’s reference range for the free T3 test. In general, a normal range of free T3 for healthy adults is between 2.0-4.4 pg/mL.
     

    It is important to note that ranges will vary slightly from person to person, and your healthcare provider will consider your overall health, symptoms and test results when interpreting your levels. It is recommended to consult with a healthcare provider if you have any questions about your results.

  • Your testing will be performed in a CLIA-certified clinical laboratory. Labcorp provides leading-edge medical laboratory tests and services through a national network of primary clinical laboratories and specialty testing laboratories. Our labs perform regular quality assurance testing to ensure our results are accurate.

  • Your results will be provided to you through our secure online portal to view or print. Results are also made available through a secure portal to the independent healthcare provider who placed your test order.  If you are accessing your results through your Labcorp Patient™ account, all users linked to the account will have access to all OnDemand test results. Results may also be provided to a local, state, and/or federal health authority; for example, many states require the testing laboratory and physician to report test results for certain communicable diseases, such as COVID-19, to local or state health departments.

     

    If you have questions or comments regarding the Labcorp Notice of Privacy Practices, or have a complaint about our use or disclosure of your PHI or our privacy practices, please contact: privacyofficer@labcorp.com, call us at (877) 234-4722 (877-23-HIPAA) and ask for the Labcorp HIPAA Privacy Officer, or send a written request to: HIPAA Privacy Officer, Labcorp, 531 South Spring Street, Burlington, NC 27215. You also may file a complaint with the Secretary of the U.S. Department of Health and Human Services.

  • Visit the Labcorp OnDemand® website to browse and purchase laboratory tests and create your Labcorp Patient™ account to view your results. All Labcorp OnDemand testing requires an order from an authorized healthcare professional. For your convenience, Labcorp OnDemand has contracted with independent professional entities (collectively, Providers) to deliver healthcare provider services. Visit a Labcorp location for sample collection; or, if using an at-home collection kit, collect your sample yourself. We’ll let you know when your results are ready and can be accessed through your Labcorp Patient™ account.