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Thyroid Monitoring rT3 Blood Test
Thyroid Monitoring rT3 Blood Test contents
Results on my.medichecks health portal
Thyroid Monitoring rT3 Blood Test

Thyroid Monitoring rT3 Blood Test

A thyroid hormone profile to get a thorough picture of your thyroid function and how well you are converting to T3.
Blood sample 4 tests included 14 working days turnaround


Key biomarkers - see full list below

  • You are taking thyroid hormone replacement therapy and want to check your thyroid function
  • You still have symptoms despite showing normal levels of TSH and T4 and want to test for FT3 and rT3
  • You want to check that you are converting T4 to T3 effectively
  • You have been advised by your practitioner to check your rT3 levels
This is a comprehensive test for thyroid hormones including reverse T3 (rT3). Sometimes a basic thyroid blood test which tests for TSH (thyroid stimulating hormone) and free T4 (thyroxine) can miss problems that could lead to symptoms of hypothyroidism. These include problems converting T4 to T3 (the biologically active thyroid hormone) as well as the production of rT3 instead of T3. This is thought to happen when the body is under stress through illness, calorie restriction or even excessive exercise. Reverse T3 inhibits the action of T3 in our cells and some practitioners believe that elevated rT3 can cause symptoms of hypothyroidism even if levels of other thyroid hormones (T4 and T3) are normal.

Please be aware that currently there is little scientific research into reverse T3 outside of an intensive care setting and there are no treatment protocols within conventional medicine. Please liaise with your specialist practitioner before ordering this test. 

This test measures TSH, FT4, as well as both free T3 (FT3) and rT3 for a thorough investigation of thyroid hormones.

3 simple steps

  • Take the test

    Take the test - either using your kit or visit a clinic.
  • Post your sample

    Send your sample in the freepost pack to our fully accredited lab.
  • Get your results

    Get your doctor reviewed results on
Expert interpretation<br>
of your results

Expert interpretation
of your results

One of our team of doctors will review your results and give you personalised advice based on your medical history, lifestyle and health and fitness goals.

Your personal<br>
health centre

Your personal
health centre

Discover the easy way to track your health through our online portal, View your results with doctor's advice, monitor any changes over time and see the improvements you can make to your health with simple lifestyle changes.

Questions? Let us help

Questions? Let us help

Our customer care team are on-hand to help you find the test that's right for you. Get in touch via phone, live chat or email.

you can trust

Trusted by the NHS and private clinics alike, you can be sure of the highest testing standards from our partner laboratories

What our customers say

We ask every Medichecks customer about their experience - read what they have to say


Our tests are not a substitute for seeing your doctor, especially if you are suffering symptoms. Our doctors will interpret your results based on the information you have provided, but will not diagnose, consult or provide any treatment. You will be advised to see your doctor for any necessary follow-up action.