Triiodothyronine (T3) is produced from thyroxine (T4) by the removal of a particular atom of iodine. When the body is under stress, for example through illness or lack of calories, a different atom of iodine is removed and reverse T3 (rT3) is formed instead. Reverse T3 attaches to receptor cells and blocks the action of T3. It is thought that this is your body's attempt to preserve energy for repair by slowing down your metabolism. Therefore there will be times when this response is appropriate. However, there may be other times when due to chronic stress or poor diet you are left with unwelcome symptoms of hypothyroidism.
Raised levels of rT3 may explain why you have symptoms of a thyroid disorder when your thyroid hormone levels are within the normal ranges.
This test is for people whose thyroid function test results are normal but who are still experiencing symptoms. It is useful for individuals who suffer from chronic fatigue and fibromyalgia as rT3 levels can also be raised in these conditions.
We send you an easy-to-use kit to collect your blood sample.
Post your sample to our lab in the prepaid envelope provided.
View results securely in your own personal dashboard.
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.
Normally T4 is converted to T3, the biologically active thyroid hormone. However, when the body is under stress (due to illness, starvation, extreme cold), it converts T4 to reverse T3 (rT3) which inhibits the action of T3 in our cells. This is thought to be a protective mechanism to conserve energy.
Low levels of rT3 are normal. A raised rT3 result may indicate that your cells are not receiving enough active T3, causing symptoms of hypothyroidism (underactive thyroid).
We will send you your Reverse T3 blood test sample collection kit together with the details of a convenient clinic where you can go and have your sample taken.
Your Reverse T3 test includes 1st class postage and packaging for you to send your blood sample directly to our laboratory for analysis. If you live in an area where you cannot rely on the post or you simply want to ensure that your sample arrives at the laboratory the following day, you may wish to send your blood sample guaranteed next day delivery for extra reassurance.
Your blood sample will be analysed at one of our chosen laboratories. You can be assured of fast, accurate results from one of our accredited independent providers of clinical diagnostic tests.
Our medical team will comment on out-of-range blood test results and give you follow-up advice where necessary. If you need it, a PDF copy of your Reverse T3 test results can be downloaded for your doctor.
Once you have placed your order you will receive login details to mymedichecks.com where you can manage your account, track your orders and view your Reverse T3 test results.
Stay motivated by filling in your online health and lifestyle questionnaire and seeing how improvements in your lifestyle can influence your test results. Your medical and family history gives us vital information when interpreting your results.