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Thyroid UK
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Overmedicated? Low T4 High FT4

Hi recently had a private test done, the results are as follows

CRP 0.90 <5.0 mg/L

Ferritin H 321.0 20 - 150 ug/L

Thyroid Function

TSH L 0.03 0.27 - 4.20 mIU/L

T4 Total 139.6 64.5 - 142.0 nmol/L

Free T4 H 28.08 12 - 22 pmol/L

Free T3 6.21 3.1 - 6.8 pmol/L


Anti-Thyroidperoxidase abs H 494.7 <34 kIU/L

Anti-Thyroglobulin Abs H 661 <115 kU/L


Vitamin D (25 OH)

Vitamin B12 301

Doctor has said to reduce my Levo, I am currently taking 150mg so will reduce to 125mg. I am not sure what the high FT4 is, or why my Ferratin is so high. I am also concerned that my antibodies have not gone down (as I had hoped) but have increased. When first tested in November they were 392iu/ml and now they are 494.7iu/ml. Not sure what Anti-Thyroglobulin Abs is. Any advice on understanding this much appreciated. I am currently taking Selenium 200mg .

9 Replies

I think, if it were me, I would reduce by 12.5, rather than 25. Because when the FT4 goes down, the FT3 will go down, too. Besides, as you have such high antibodies, it's possible that the over-range FT4 has nothing to do with the dose you take, and is due to a Hashi's hyper swing. In which case, it will go down again by itself. So, you don't want your doctor altering your prescription, because then you will have trouble getting it raised again!

What were your results on the last test? And how much were you taking at the time?

Anti-thyroglobulin abs, are just more Hashi's antibodies.


Hi Greygoose,

Last test TSH was 3.05mu/l and I was taking 75mg

I saw my GP yesterday and had my results from my last bloody test (same as private test for TSH) so he knows it was low. He suggested taking alternative days at 125mg. Of course he doesn't know the other results as they only test TSH on the NHS.


You went up from 75 mcg to 150 mcg in one go?


Oops no, sorry. started at 75, then increased myself to 100mg (after GP said my TSH at 5.25 for fine.......then next time he increased to 125mg which resulted in TSH 3.25 and I then insisted on increasing it to 150 to get it down to near 0. So my own fault really. He has now suggested I take 125mg one day and 100mg the next day which I think is sensible.


No, not your own fault at all. He should have been doing more to help, and testing the FT4. Well, try it his way now, and see what happens. But, it's somewhat doubtful that your TSH would go from 3.25 to 0.03 on that last increase. It could still be something to do with your Hashi's.


Thanks Greygoose, I will give it 6 weeks on the lower dose and then do a private retest. GP said to make my next appointment in the Autumn (October) but I think given the results this may be too long.


I think so, too! :(

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Free T4 (FT4) is a more useful measurement than Total T4. Your FT4 is considerably over range which is why your GP has asked you to reduce dose. TSH is suppressed because FT4 and FT3 are high. Thyroglobulin antibodies also denote Hashimoto's. Are you 100% gluten-free?

High ferritin indicates inflammation or infection somewhere in the body but CRP which is also an inflammation marker is low so it may be you had a cold or virus at the time of testing.

If you have symptoms of B12 deficiency in b12deficiency.info/signs-an... go to healthunlocked.com/pasoc for advice about supplementing.

You haven't included the vitD result.

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I managed to delete the Vit D, it was 111 so okay.


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