Thyroid Panel with Reverse T3 Blood Test

Item # LC100044

Thyroid Panel with Reverse T3 Blood Test  - Life Extension

Thyroid Panel with Reverse T3 Blood Test

Item # LC100044

The Thyroid Panel with Reverse T3 Blood Test will help you determine whether you have any of the three “usual suspects” of an abnormal thyroid function: not enough production of T4, reduced conversion of T4 to T3, or greater production of inhibitory reverse T3.

The panel contains the following tests:

  • Thyroid-Stimulating Hormone (TSH) - Evaluates overall thyroid function
  • Total Thyroxine (T4) - Measures the total amount of T4 produced by the thyroid gland
  • Free Thyroxine (T4) - Measures the amount of T4 available to the cells and tissues
  • Free Tri-iodothyronine (T3) - Measures the amount of T3 (the active form of the hormone) available to the cells and tissues
  • Reverse T3 - Measures the non-functioning form of the active hormone T3

This panel was designed to look at the three primary underlying causes of suboptimal thyroid function:

  1. Insufficient production of T4
  2. Decreased conversion of T4 to T3
  3. Increased production of inhibitory Reverse T3

Your thyroid gland sits in the lower portion of your neck and acts as the metabolic throttle for every cell in your body. Daily stress, age and poor diet can interfere with the way your thyroid hormones function, affecting your metabolism and energy regulation. An estimated 27 million Americans have thyroid disease, and about 13 million of them are undiagnosed.1 Since symptoms can often be vague such as fatigue, depression, and weight gain, many people are not tested for thyroid dysfunction.


Fasting is not required for this panel. Take all medications as prescribed.


  1. J Am Acad Nurse Pract. 2004 Oct;16(10):422-5.

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.

SALE: $90.00
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I plan to purchase this yearly. Both my doctor and I trust Life Extension blood testing.


My practitioner changed my thyroid meds! Needed to monitor all the on-going changes.

Lou the Texan, Southern Texas

Comprehensive Blood Test, easy and fast. I get my results in a timely fashion

Sue R, Thornton, CO

Good lab panel. Recommended by my doctor. Results are mailed and emailed.

Sue, Thornton, CO

Thyroid Panel with Reverse T3 Blood Test

  • $120.00
  • Sale $90.00
  • Save 25%

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