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Dosing advice - transitioning from NDT to T3 only


I need some advice. I have Hashimotos and the faulty DI02 gene that does not convert T4 to T3. I am wanting to change over from Thiroyd to T3 only. Should I drop back and start with 5mcg (it'll be 6.25 as have 50 pills that I am splitting) every 4 hours or so, or should I try and match what I was dosing with Thiroyd, I was up to 3 grains.

Many thanks

9 Replies

I have also read about taking in one dose to saturate. This is something I will try.


Charliescat, there's 27mcg T3 in 3 grains so that's the least you are likely to need. 3 grains is roughly equivalent to 75mcg T3. 3 x 20mcg daily is the dose prescribed for patients after thyroidectomy.


Thank you.

I haven't had a thyroidectomy. I was previously on 200 Levo and didn't feel well. I've been taking the NDT for 5 weeks and had gradually increased to the 3 grains. I've then had the news RE the gene test. I don't feel like I was optimal on three grains but was having the odd day with some energy and clearer thinking. I was at the point of holding for 4 weeks, then getting blood tests but have been advised due to the gene issue T3 may be the way to go.

I am also considering combining the two, the NDT and T3 but not sure how to go about this either. Any advice for combining the T3 with NDT?

My goodness, it's all so confusing, especially with the fog!


Charliescat, it would have been better to titrate Levothyroxine while you built up your NDT dose. You've gone to 3 grains rather quickly and 5 weeks isn't long enough to have absorbed the first dose properly yet. Check out this link thyrophoenix.com/adjusting_...

27mcg T3 in 3 grains NDT will overcome a T4 to T3 conversion issue. It's not necessary to take T3 only unless T4 makes you ill. I would advise you to stick with NDT and have a blood test to check levels in 2-3 weeks. It can take up to 6 months to successfully transition from T4 to NDT.

I don't advise you to start T3 only, but if you do, start at 3 x 20mcg.


Thank you for the link. I've come across that before. I followed a different protocol and increased every 7 to 10 days or when hypo symptoms returned, I then intended on holding at 3 grains for 4 - 6 weeks to see what was happening.

I am being impatient with wanting to feel better and thank you for your advice. I am due a blood test in two weeks so will see what is happening then. Although, I have read that when you have the conversion issue (I have inherited from both parents), blood tests can appear normal and that it is the brain not receiving the T3. Brain fog and fatigue being the two most severe symptoms.

As far as I understand it, even on NDT I would still need to convert the T4, which will be difficult for me as, according to the lab I have a loss of functionality of 70%.

I think the best course of action is to stay on the NDT and very gradually introducing the T3.


If you don't convert, then it is like taking nothing, except the t3 portion of the ndt. I would drop the ndt and take the equivalent amount of t3...waiting a week or so between raising. google Cytomel dosing info and see the dosing recommendations.


Thank you Faith63. Gosh, I am so confused. I have now got to the point of seeing someone privately. I have an appointment on Friday with a private endocrinologist, who I have heard good things about. I am feeling worse and worse by the day and think that you are probably right about the T3.


It would be a miracle if this doctor knew how to treat non conversion with t3 only. They don't learn that in medical school. I have beeen thru 4 Endo's in 4 years. If this doesn't work, may have to self treat. Good luck with your appointment!


So would I start taking 75 mcg straight away?


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