Thyroid UK
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Help please newbie

Been on levothyroxine for 10 years for underactive thyroid. I am 46

I take 150 of levothyroxine. I have felt so so tired, freezing cold dispite house being boiling, a little breathless at times and was absolutely sure something was wrong with my thyroid. Got blood results today

Free T4 is 16

TSH IS 0.03

T3 not done

I am pretty lost with results and DR not concerned what do you guys think I haven't a clue and would so appreciate your help xxxxx

2 Replies

Without knowing whether the low looking free t4 is actually converting to free t3, your doctor is just guessing. The tsh is fairly irrelevant as so many things seem to make it go down....

dr toft. ( an nhs semi retired endo) says in his book. (endorsed by the British medical association) that free t4 needs to be at the top of, or just over range in order for you to do the t4 - t3 conversion thing. Heres a link to the book on kindle...

Suggest you get your free t3 measured.... And see where you stand..... Details of private tests where you deal direct with the lab yourself are here:

Breatlessness could be linked to low iron... Any idea about your levels? How about Ferritn, d3 and b12? It all makes a difference.

You can work it out, ask as many qestions on here as you like....

Xx g


Your TSH is low so this means the body is not looking to make anymore T4 as it senses there is enough T3 around. Higher TSH increases T4 to T3 conversion.

Because you don't have the FT3 the full picture cannot be seen and so we have to guess a bit.

So could you have plenty of T3 sitting in the blood but it is not going into the cells ? This is a strong possibility. This would also mean the TSH switches off.

If this is the case then more thyroid meds probably isn't the answer. It is a case of finding out why you are not absorbing the T3. Low iron can be a cause and poor adrenal function = there may not be enough cortisol to take the T3 into the cells, OR you might have excess cortisol which causes blocking to the T3.

It would be good to get the 24h saliva adrenal test done to see how the adrenals are working, a full iron panel and the FT3 levels.


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