Thyroid UK
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Someone else talking about rT3

Found this:

Not sure if I can paste this a click-through link; if not then it will be a copy and paste job, sorry.

Scroll down to 3rd article

Someone who seems to have no problem with T3 for a change.


12 Replies

That is very interesting, I am going to get my Rt3 tested, if only just for interest. I am not doing particularly well on Levo. It may give an explanation. Thanks for posting.


I asked my endo to carry out a RT3 test, he refused, said it was useless and that he didn't think it could even be done but he would ask the pathologist! When I went for my bloods, the pathologist said she'd researched RT3, it's not something they can do and there is no-one in the UK who could interpret the result!!!


If you do a quick search, does test for this - but only in Europe, via Genova Diagnostic. Genova UK have a test kit - but probably a phonecall would be needed to know if they'd ship from the UK to Europe to get it done. Of course, you'd have to 'go private' and pay for this yourself! There may be other GPs inside the UK who can do this, though.


Genova Diagnostics do carry out the test, I am having a full thyroid done, along with full iron panel, with them before my appt with my requested second opinion endo (who is apparently NDT friendly!). I have just had the 24hr saliva done with them through Dr. P. I think Blue Horizons do it too and you don't need a doctor's order with them. (By doctor's order I mean with Genova they ask who has ordered the test and it is sent back to them rather than directly back to you). It's a ridiculous statement from the NHS endo/pathologist that this test can't be carried out/interpreted.


Thanks for this one, Hypho. It's the easiest explanation I've come across as to why T3 is preferable to T4 if the T4 meds don't seem to work.


Testing it is all very well, but if it is high, then to do something, you will have to do it yourself, and if you don't know what the cause of the problem is, then it may well just return!

There is a lot of info online, would suggest looking for a specialist forum for more detailed help, it's not something you should even think about if you are not the researching and detailed technical type. It means taking T3 exclusively, (NOT slow release) and it isn't a joy if only for the 4 or 5 times daily dosing, as well as never feeling sure what is going on, and whether your are actually hypo or hyper!

Testing is (or was then!) expensive.

I went through this process almost 3 years back, and it meant lots of ups and downs, and one false alert of being hyper (it was actually not) made me "bottle out" for 3 months before trying again.

My TSH, T4 and T3 were not showing me badly hypo, more just sub-clinical Hypo, but I had a lot of Hypo symptoms, hence the reason I tried clearing the RT3 as a solution, and yes, It did "clear" after a bit over 12 weeks, when I suddenly went hyper and had to cut back, but within about 6 months of going back to normal I felt hypothyroid again, (I have chronic pain, a likely source of the problem, and can't therefore lose the source of my problem) so went onto NDT which has generally got things under control since.

Put it this way, I haven't planned on doing it again.


Thank you, I can only get FT3, FT4 and TSH done and have to pay for RT3 which I will do to ensure that I don't have a problem but as I take a natural thyroid extract I have a feeling that it won't be the cause of my problems :(


Genova do the RT3 test in amongst their Full thyroid scan of blood if it is also requested at the time for an extra cost of course. This also means you get a full picture of results from the same blood sample.

Mine came back very low and was therefore concluded not to be the issue. I have since supplemented with selenium and iodine (confirmed previously no anti bodies) and am feeling slightly better. Also keeping sugars of all types to a minimum is helping too.


rT3 test is available privately from at least Genova, have a look here:

However, the link mentions "Free rT3" and I do not recall ever seeing that mentioned before.



Thanks Guys but I live in Oz - moved here 18 months ago and the sunshine is heaven but causing havoc with my thyroid LOL.


Remember continuing hypo symptoms and not being able to tolerate increases in meds can be down to cortisol issues (either low or dysfunction) or low iron.


There certainly are clinical ways to prove that thyroxine is not working if they would only use them.


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