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Thyroxine (T4) Blood Test
Item # LC001149
Measures the total amount of the thyroid hormone T4
Thyroxine (T4) Blood Test
Item # LC001149
Measures the total amount of the thyroid hormone T4
This test measures total thyroid hormone production by assessing your level of the thyroid hormone thyroxine (T4). High T4 levels occur in hyperthyroidism, while hypothyroidism is characterized by low T4.
| Thyroxine, otherwise known as T4, is a hormone produced and secreted by the thyroid gland. At the tissue level, T4 is converted into the more active form of the hormone called T3. For this reason, T4 is considered a measurement of total production of thyroid hormone. Hypothyroidism is a condition where T4 blood levels are low. This causes cellular dysfunction and metabolic breakdown. Symptoms may include weight gain, constipation, dry skin, and hair loss. Low T4 levels may even lead to the development of chronic diseases such as heart disease and diabetes. Hyperthyroidism is the term for elevated T4 blood levels. Symptoms can include anxiety, insomnia, heart palpitations, and bowel discomfort. Instructions Fasting is not required for this test. Take all medications as prescribed. Note For a more extensive evaluation of thyroid function, Life Extension® offers a Comprehensive Thyroid Panel. |
The laboratory services are for informational purposes only. It is not the intention of National Diagnostics, Inc and Life Extension to provide specific medical advice but rather to provide users with information to better understand their health. Specific medical advice including diagnosis and treatment will not be provided. Always seek the advice of a trained health professional for medical advice, diagnosis or treatment.
Both the physician and the testing laboratory are independent contractors with whom National Diagnostics, Inc makes arrangements for your blood tests. Neither National Diagnostics, Inc or Life Extension will be liable for any acts or omissions of the physician, the testing laboratory, or their agents or employees.
A clinician's order is required for many tests. Where applicable, an independent clinician will review your test request and determine whether to authorize the test, if appropriate. For additional information, see PWNHealth Terms of Service.
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