Extended Thyroid Profile (FT3, FT4, TSH,Total T3,Total T4)

Specimen Required

3-5cc Clotted Blood or Serum

Fasting Required

Purpose of the Test

The extended thyroid profile test measures the levels of various hormones in the thyroid gland, including free T3, free T4, total T3, total T4, and TSH. The test is used to evaluate the overall function of the thyroid gland and to diagnose thyroid disorders.

When this test is required

The test may be ordered if a person has symptoms of a thyroid disorder, such as weight changes, fatigue, heat or cold intolerance, irregular heart rate, and hair loss. It may also be ordered if a person has an enlarged thyroid gland (goiter), a family history of thyroid disease, or if they have been diagnosed with an autoimmune disorder such as Hashimoto’s thyroiditis or Graves’ disease.

What the Test Detects

The extended thyroid profile test measures the levels of various hormones in the thyroid gland, including free T3, free T4, total T3, total T4, and TSH. Free T3 and T4 are hormones that are not bound to proteins and are available to be used by the body’s cells. Total T3 and T4 measure both the free hormone levels and the levels of hormones that are bound to proteins. TSH is a hormone that stimulates the thyroid gland to produce T3 and T4.

Preparation for the Test

There are no specific preparations required for this test. However, it is recommended to inform your healthcare provider about any medications or supplements that you are taking as they may interfere with the results of the test. In some cases, the healthcare provider may ask you to avoid certain medications before the test.

Sample Requirements

The test requires a blood sample, which is usually taken from a vein in the arm.

Additional Notes

Certain medications such as thyroid hormone replacement therapy, birth control pills, and steroids may affect the results of the test. It is important to inform the healthcare provider of any medications or supplements that the person is taking. Additionally, other medical conditions such as pregnancy, liver disease, and kidney disease may affect the levels of thyroid hormones in the blood.

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