Advice on changing from T4&T3 to T3 only - Thyroid UK

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Advice on changing from T4&T3 to T3 only

I've been on 125mg of T4

And 30mg T3

How do I go about changing to T3 only?

Can I do it straight away? Or does it need to be gradual?

Thank you all in advance of any replies 🎂

Free T4 -16.0 pmol/L 12-22

Tag <0.02mU/L 0.27-4.2

Free T3 6.4pmol/L 3.1-6.8

At end of oct 2016,

I feel I may be thyroid resistant having always been tired, and originally labelled M.E. then graves, with RAI treatment 22 years ago

13 Replies

Suin, Please give some information about why you want to change to T3 only. Posting your most recent thyroid blood test results, taken whilst on your current medication would also be helpful to those offering suggestions.


Thanks I've added some results redapple


Thanks Elliot

Ah I just feel at the end of my tether and the more o read about thyroid resistance, the more I see me. Even when all bloods are good, I'm not 😐



125mcg Levothyroxine is equivalent to 40mcg T3. FT3 isn't far off top of range so probably best not to increase by 40mcg but perhaps by 20mcg and check FT3 in 6 weeks to see whether you need to increase.


Thanks clutter, I'm on 125mcg T4 and

30mcg T3

So should I take only

50 T3 or do u mean 30plus 40?

Sorry if u could think straight it would help



I would try 50-60mcg split over 3 doses.

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Ok thank you, I'm concerned where I'll get bloods done as private endo has been postpone appointments since July as is off sick, though I'm still getting T3 through nhs so I'm lie low and keep quiet atm 🕵🏻



Will you have sufficient T3 to double your dose?

You can order private tests via Blue Horizon Thyroid Profile Plus 6 covers TSH, FT4 and FT3.

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Yes I've bought T3 online to cover shortfall, though should I stick to one brand?

I may well need to have bloods tested online as gp will hassle me on results if they're anything out of the "norm"

Yet happy to ignore when other results come back Low 🙄

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Suin Before you change your meds, I would look at your iron panel. This could very well be causing you problems, particularly fatigue, as it is far from optimal

Ferritin: 60 (13-150) This is far too low. An absolute minimum of 70 is needed for thyroid hormone to work properly, half way through range is recommended (that would be 81.5), and I've read that 100-130 is best for females.

Iron: 12.3 (10-30) This is very close to the bottom of the range.

Transferrin: 2 (2-3.6) Just scraped into range

Saturation: 24.4 (30-40) This is below range and has been marked Out of Range (OOR) - has your GP said anything about that? I think you should be talking to Your GP.

How are your other vitamin and mineral levels at the moment?

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Seasidesusie thank you, how did you 'mention ' me?

My gp seems to be happy to ignore most things I bring to her attention.

These were my results when supplementing 4 months ago:

Vit D 132nmol/L High( >50nmol/L <30nmol/L)

Serum iron 9umol/L (10-30) Low

Transferritin 1.90g/L(2.0-3.6) Low

Ferritin 95ug/L

Transferritin saturation 19%

B12 >2000ng/L (197-771) High

Folate 14.1ng/L (4.6-18.7)

Free thyroxine 12.6pmol/L (12-22)

TSH <0.01 mIU/L (0.27-4.2)

Free T3 4.3 pmol/L (3.1-6.8)

All she was concerned about was,

high b12

High bit D and low TSH

Much thanks 🎄


Seasidesusie thank you, how did you 'mention ' me?

I have magic in me Suin :D

You put @ directly in front of the member's name (no space) then a list of possible names will pop up, you click on the one you want and it highlights blue, it will show up in your message without the @ and the name in blue, then the member gets sent an alert that they have been mentioned.

Your GP seems as caring as all those at my surgery, depressing isn't it?

With those results, your Vit D wasn't too high, it was perfect - recommended is 100-150nmol/L. So if you were supplementing you should have gone onto a maintenance dose to keep it there or kept to the same dose if it wasn't particularly high.

B12 at 2000, yes that was high but excess is pee'd out anyway. But if you were supplementing you could have reduced the dose to save peeing out money!

I have a GP who goes on about suppressed TSH, even when I point out that FT4 and FT3 are in range it doesn't matter, only the suppressed TSH matters. I just ignore requests for tests now and do my own thing - testing and tweaking meds (I added a bit of T3 and lowered Levo a bit).

And as some of your iron results were below range she really should have investigated further. I sometimes wonder why there are ranges at all when they get ignored by the very people who should be able to interpret the results in relation to the ranges!

I am not as au fait with iron panel results but I will tag in humanbean because she knows more about it. Hopefully she's about and can respond to your current results.

Humanbean - can you please look at the picture in the first post and see what you think? I always thought saturation should be around 30% but that range is only 30-40% anyway, and all the others look low. I did wonder about iron deficiency anaemia when looking at this chart but Suin's transferrin is low not high, maybe ferritin isn't low enough, and there's no TIBC. Then I looked at ACD and as usual I'm unsure.


SeasideSusie woo hoo I wondered how ppl did that. I'm Magic too ✋🏼

Thanks so much for all your input, I honestly think that's the highest my iron has ever been. I've been born tired😴

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