I am currently switching from 5 years on NDT to Thyroxine.
My results 24hrs after both meds are:-
TSH 0.01 (0.27-4.2)
FT4 17.2. (12-22)
FT3 4.4 (3.1-6.8)
This is on 60mg NDT and 100mg Thyroxine. I’m planning on stopping the NDT and replacing with 50mg Thyroxine to give better results. I’m still feeling tired but have lost the overheated feeling.
Can it take a while for TSH to pick up after being NDT for many years?
I really don’t know to be honest. Sorry. I personally would feel uneasy swapping about with anything medically without the help of my GP or an Endocrinologist. You are brave to do this on your Tod. I myself am on Levo Thyroxine and take many supplements and feel just about right, but really could do with a bit more energy. Good luck 😊
Hi Biddy, I wish I had your faith in doctors/endos.
If I had listened to them throughout my 20+ years with Hashimoto's I would probably be dead by now!
I have learned more from sites like this one, and my own research than all the incorrect and spurious information the medics have fed me over the years.
Just a few days ago I had a massive argument with my GP who is threatening to reduce my 100mg of levothyroxine because my TSH is below the "normal" range even though my FT4 is only 39% within range and my FT3 is just 5% within range.
I am also on Metformin ( for diabetes which might even have been caused by long term insulin resistance due to lack of T3 over a long period ) which actually skews the TSH result by enhancing the effects of thyroid hormones in the pituitary, giving a falsely low reading. My GP actually said "there is no indication that you are under medicated.....quite the opposite" when my body is clearly crying our for thyroid hormone at cellular level.
It should not be up to the patient to have to provide their doctor with articles from the Journal of Endocrinology in order to ensure that their doctor does not erroneously reduce their meds and damage their health further than the Hashimoto's already has!
I agree. That is why I am happy to self medicate - I have control! They do have a clue about thyroid.
Yes it’s a massive struggle. I have been there too. What with hormones and leaky gut on top it’s an absolute nightmare. I’m with my third GP surgery since finding out I have Hashimoto’s. It pays to move some times. I’ve had it for over twenty years too - took ten years to find a GP to diagnose it!
Once we are on meds TSH is not of so much importance. The hypo symptoms are caused by low FT3 mostly. Some folks never get their TSH to increase so it may not come back into range.
So I am correct in thinking my FT4 and in particular FT3 need to be higher.
It depends where you feel well. FT3 could be higher but ft4 could be fine where it is. However if it was 24 hours between your last dose and the blood test you have a false low FT3 result and it would normally be higher. I would have a think about what you are doing, why you are doing it and what you are hoping to gain from switching from NDT. It is not easy to find the correct levo dose. Then if you are not converting properly you need to consider adding T3 tablets. These have to be sourced and again dosages need to be worked out.
Can it take a while for TSH to pick up after being NDT for many years?
It can indeed. In fact, it might never rise, because you could have down-regulated your pituitary/thyroid axis. And, whilst you have the T3 in the NDT, that wouldn't matter. But, going on to levo only, it could affect your conversion. Why are you doing this?
My results 24hrs after both meds are
If you left 24 hours between your last dose of NDT and the blood draw, you now have a false FT3 result. It should only be a gap of 8-12 hours.
This is on 60mg NDT and 100mg Thyroxine. I’m planning on stopping the NDT and replacing with 50mg Thyroxine to give better results.
Why do you think that will give better results? 60 mg is more like 100 mcg levo than 50, so you're giving yourself a reduction in dose, which could bring your FT4 level down, but will certainly reduce your FT3. I'm afraid I fail to follow your logic, here.
Thanks greygoose. That makes sense. I was thinking taking the NDT out of the dose may increase my TSH, which would increase conversion of the FT4, thus increasing FT3.
Probably more NDT is the way to go then?
Well, it might and it might not. I think it probably wouldn't. There are so many reasons for poor conversion. Low TSH is just one of them. Why did you start NDT in the first place? Wasn't it due to poor conversion? That's why most people start it. But, as your TSH has been suppressed for years, the odds are that it won't rise.
Personally I would go back to NDT only, wait six weeks, then do labs properly, and then decide what to do according to the results. Dosing by symptoms is all very well, but so many symptoms can be from both too much or too little hormone. And that's where a lot of people get totally lost. Labs can help guide you in the right direction. 
Thanks greygoose. I started with NDT as my FT4 and FT3 were both low and my GP would not treat me. Although I feel so much better I have always felt overheated on whatever dose of NDT I take. That’s why I think NDT does not suit me. I do actually feel a lot better on the combined dose, but I still feel tired & think there is room for improvement.
Thank you everyone for your help, time & support on Boxing Day x
Could be that you feel over-heated because you've always been under-medicated. But, you need correct labs to know where you are.
Even making allowance for the too long gap between the last dose and the blood draw, it would probably only take you up to just over mid-range. Most hypos need their FT3 higher than that.
I have had near perfect blood results on NDT but still felt overheated, that is when I decided it wasn’t for me and started to introduce Thyroxine. I also used to leave 12 hours before bloods when on NDT only.
What do you call a perfect blood test result? If you didn't feel good, then it wasn't perfect for you, was it? There's no set of results that is perfect for everyone, whatever doctors might tell you.
Why did you stop leaving only 12 hours?
On 3 grains FT4 16.4 & FT3 6.3 (same ranges). However, I felt continually overheated, as I did on lower doses. I have lost that feeling now.
I stopped leaving 12 hrs as I now take Thyroxine. In hindsight I should have split the dose. Even then my FT3 would have been low though.
I think it's pretty clear that you need the T3. So, have you considered trying T4+T3, rather than T4 only?
Yes, it would have been a good idea to split the doses to get a clearer idea of your FT3 level.
I'm still on levo only but have often felt overheated even when undermedicated too. (on top of the usual hot flushes that I've had for many years!)
Instead of the more common hypothyroid slow heartbeat, mine is on the upper end of normal or even higher (usually between 80 and 90 bpm, occasionally above after only slight exercise).
Yet the last blood test and the rest of the symptoms seem to indicate I'm still undermedicated.
(T3 and T4 are within range, but TSH seems to be sticking on the low side, as expected).
fixit , All sorts of crazy things seem to happen with thyroid problems, but if I were you I wouldn't go back to Levo only.
Quite agree.
Thanks Jnetti that’s interesting.
What level is your blood sugar 2 hours after eating? I was overheated for years and it turned out to be that my blood sugar was too high.... main problem for me was starchy carbs, which points to a lack of gut flora.
I also had low insulin production, high resistance, caused by low folate, In turn caused by defective mthfr gene.
No longer hot, no longer struggling with high blood sugar and i have list 3 stones without dieting. I upped my folate using methyl folate, NOT folic acid.
Whew! Hope this gives you some clues.
G. X
Very interesting galathea. I will look into this.
Galathea, did you change your diet to reduce starchy carbs?
Well i stopped eating them for a while, my main problem was rice, which would raise my blood sugar levels to around 27 for a couple of days. I took several courses of probiotics. (Vsl 3), i make and drink kefir ( fermented milk). And i drink kombucha. ( fermented tea) all in an effort to keep my gut flora happy. ( i had previously taken many courses of antibiotics which wipes out gut flora)
I can and do eat rice now, without much in the way of adverse effects. But i am quite thorough about keeping up with kefir and the knombucha. Its been several years since my blood sugar climbed high, it stays under 9 these days and i no longer feel hot all the time.
The aim for a TSH result is the lower the better i.e. 1 or lower. Your TSH looks o.k. At present your FT3 looks a bit on the low side. The following may be helpful:-
NDT and Thyroxine 
Started NDT today after 15+ years on Thyroxine
Is NDT better absorbed than thyroxine/liothyronine combo?
Unable to tolerate sufficient Thyroxine, T3 or NDT
Why does ferritin have to be high for NDT but not for Thyroxine?
