Reverse T3

[teenarocks]

If I am taking T3 (Liothyronine) every day, would a Reverse T3 lab test give me any reliable information? Thank you in advance for your answers.

[helvella Administrator Thyroid UK]

Reliable? Well, there is no particular reason to question the test itself.

I question the interpretation of reverse T3 testing in anyone.

But if you are taking T3, it is questionable what useful information you could draw from it. And even if it did appear to say "more L-T3/less L-T4", well, you potentially can try that anyway and see whether you feel better.

[teenarocks in reply to helvella]

Thank you for the clarification. I wasn't sure about the test.

[DippyDame]

An rT3 test tells you nothing other than it's high or low but there are many reasons for that ...but only one is related to thyroid function

rT3 is the product of excess unconverted T4, it is the metabolically inactive form of T3.

You don't need an expensive and lengthy rT3 test to judge T4 to T3 conversion status you can do that by comparing FT4 with FT3, before any T3 is added....high FT4 with low FT3 indicates poor FT4 to FT3 conversion

What "reliable information" are you hoping to gain?

Maybe...

T3 lowers both FT4 and TSH.

FT3 must remain within reference range to avoid overmedication

Any help?

Are you taking T4/T3 combo or T3-only?

Don't be drawn into thinking an rT3 test is of importance.

[teenarocks]

Thank you for taking your time to explain this to me. I wasn't sure if the Reverse T3 test would be helpful in some way or not but now I will not pursue it.

[helvella Administrator Thyroid UK in reply to teenarocks]

You meant to reply to DippyDame

[DippyDame in reply to helvella]

Thank you!

[DippyDame in reply to teenarocks]

You're welcome.