Thyroid UK
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NDT Dr has said to take 6 x1 grain??

Hi All

I went to see my Dr today, and explained I have NDT and want to make the switch over, but still wanted regular blood tests and management from him.

He was very happy to support this decision, but when I asked about a doseage, he said to take 6 x 1 grain tablets and see how I get on. Originally he said 8 X 1grain, and when I said that is a lot he the said the 6.

This still seems VERY high????

I currently take 300mcg of levo.

Any help or guidance would be appreciated.

11 Replies

hi , NDT 1 Grain = 38 mcg T4 and 9 mcg T3 . T3 is 4times stronger than T4 .

So 1 grain NDT =74 mcg thyroxine

300 mcg thyroxine + 4 grains NDT

However this is still s large dose . I suggest the book and website " stop the thyroid madness "

They have a very good section on dosing and how to do it .

Your Doctor probably doesn't know this about this .

I take 3 grains of Armour in 3 doses . 6.00 am ( before getting up at 8.00 ) midday and 4.30 .

CHEW UP and swallow with water , It increases absorption .

good luck



Thanks Alison.

I was planning on stopping the levo and just taking the Armour.

I am also taking IRON, B12 injections & Folic Acid, as these results were very low.

Sounds like that book/website is a must read - off to amazon to purchase :-)



1 grain = approx. 75 mcg of Thyroxine hence if you were on 300mcg you need around 4 grains of NDT

My husband was on 350mcg of Thyroxine and now takes 4.5 grains of Armour


When switching it may also be better to start on a lower dose and build up. NDT works in a different way so you may not even need as much as 4 grains.

Good on you for checking here first and not blindly following the GPs instructions.


Thank you everyone! A big help!


DO NOT just exchange the levo for the NDT, it doesn't work like that!! The sudden taking of T3 will upset your system and put you off altogether!! Build up from 25 mcg over a few months.


:-/ ooopppsss - thanks will do.

So increase ndt whilst still taking levo until upto say 3 grains then reduce levo or stop levo?

Good job you guys are here - my g.p said to just switch!?


Stop your levo about a week before starting the NDT.


sorry now I am confused?

Should I keep taking my normal dose of levo whilst increasing the ndt gradually?


sammi3, I think there is no right or wrong way, there are no absolutes about taking thyroid meds and/or swapping over from one to the other. My experience with moving from mono T4 to combo T3 & T4 for instance, was simply to add the new T3 to the existing T4. Others here have found they reduced T4 to accommodate the new T3. So we're all different. Then last week I changed from T3&4 to NDT, and having calculated the equivelant dose (3 grains in my case) I simply stopped the T3&4 one day and started the NDT the next, with absolutely no problem. A week later I've added in another half grain, again no problem, no hyper symptoms even though there will be residual T4 in my system. So the point I'm making is that there are no absolutes and what's right for one might be wrong for another and vice versa. Definitely your GP made an error with his equivelant conversion but other than that, you know how you react to changes in your meds, so let that guide your conversion. :-)


Stop your levo about a week before you start your NDT, don't take both at once unless you really feel you need extra T4 (levo)


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