Thyroid UK
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Thyroid test results

Hi thyroid gurus,

so, I've been advised by you lovely lot to post my thyroid blood test results for a thorough analysis by you lovely, knowledgeable lot. Here you go, the latest (post-2 months of Erfa, currently on 2 grains - not reached optimal dose yet as I still feel exhausted and pained):

Free T3: 3.9pmol/L

Free T4: 12.4pmol/L

TSH: 0.04 mU/L

Thyroid Profile: 442

(NHS tests taken Monday 22nd Sept)

Previous bloods taken before Erfa (April 2014):

Free T3: 1.1 nmol/L

Free T4: 13.2pmol/L

TSH: 1.38mIU/L

(Done by the Doctors Laboratory, private healthcare)

Lost on the reduction in TSH. I know its not the result to usually focus on, as its usually a false indicator of thyroid function, but its reduction does worry me.

Any comments and advice much appreciated. I don't feel well at all ( SEVERE fatigue still), so still looking for the miracle sweet spot with the Erfa dose. Any experience of this out there?



15 Replies

Clutter asked you a week ago to get your ferritin, B12, folate, D3 checked as well. Any results on those? Because without optimal on these, you can take all the ERFA you want and you won't feel well. In fact, you'll feel worse.


The NHS GP I saw refused to do these tests. I am just waiting to see my private functional medicine doc to get these levels checked.


Jen, we really need the lab ref ranges (the figures in brackets after your results) to interpret but I'd say your FT3 is low. TSH will be low because the T3 in Erfa suppresses TSH.


Hi, see below with the reference ranges, thanks.

NHS tests taken Monday 22nd Sept:

Free T3: 3.9pmol/L (2.6 - 5.7)

Free T4: 12.4pmol/L (9.2 - 21.0)

TSH: 0.04 mU/L (0.30 - 4.40)

Previous bloods taken by Doctors Laboratory before Erfa - April 2014:

Free T3: 1.1 nmol/L (1.3 - 3.1)

Free T4: 13.2pmol/L (12 - 22)

TSH: 1.38mIU/L (0.27 - 4.2)


That range 1.3 - 3.1 nmol/L looks far more like a Total T3 range - including being the appropriate units.


Free T3: 1.1 nmol/L 3.1 - 6.8 pmol/L

Free T4: 13.2pmol/L 12.0 - 22.0

TSH: 1.38mIU/L 0.27 - 4.2

(Done by the Doctors Laboratory, private healthcare)


(I've added in the usual reference intervals for this lab.)

If you haven't taken any thyroid medication ever prior to these results they would suggest a form of central hypothyroidism due either to a failing pituitary or other causes such as severe illness, stress or depression. If you haven't seen an endocrinologist to check out pituitary function I'd try and get a referral. You can supplement with thyroid hormones but there will be reduced T4 to T3 conversion (due to the low TSH) and you will still have other potential problems with other pituitary hormones.

This shows up in your second set of numbers where the TSH drops to 0.04 even though your fT3 and fT4 are still very low. If you TSH remains at these low levels for a long time it may be down-regulated making your condition a bit worse. Your doctors should be investigating your pituitary function if they haven't done so already.



It look as though you meant pmol/l not nmol/L for T3 or you'd be really, really hyper.


Be aware that the document UK Guidelines for the Use of Thyroid Function Tests produced and endorsed by the combined minds of the Association for Clinical Biochemistry, the British Thyroid Association and British Thyroid Federation managed to make exactly the same mistake:

TSH 0.4 – 4.5 mU/L

FT4 9.0 – 25 pmol/L TT4 60 – 160 nmol/L

FT3 3.5 – 7.8 nmol/L TT3 1.2 – 2.6 nmol/L


Despite my best efforts, I have been unable to get them to correct it.

If anyone gets this document quoted at them, please point out this ridiculous error. It might make it more difficult for them to claim its perfection.



I checked the numbers a measurements and it does say nmol not pmol. I have added the reference ranges above which might help. The conversion between the two do not seem to work - I tried putting my results into a conversion tool online so that I could state them all in the same measurements, but the numbers came out so high or low that I disregarded them and that's why I stated the results above as they are printed on the lab reports.


nmol/L is usually used for total T3, not free. and the range is usually about 1.2-2.6 nmol/L. Either the nmol/L is wrong and you have very low free T3 (with correct ref range) or they tested total T3 and put in the ref range for free T3. Not very useful either way. I'd query it.


Thank you Jim. I am seeking a private Endo currently, as the NHS does not consider my test results to be indicative of a thyroid problem (madness). I will definitely look into pituitary function with them. Much appreciated.


Without Ferritin, B12 ,Vit D3 all the other results are meaningless because you CANNOT utilise any form of T4 if your ferritin is below 70


Your FT4 and TSH will drop when taking NDT and your FT3 will rise, which looks as though it has been.


The T3 result is the only one that means much when you are taking T3. You are still quite low in the range. This would suggest you could take a bit more ERFA without problems.


Thanks for that. I am slowly upping the dose, so will see how it progresses.


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