Changing from NDT to T3/T4 combo : Hi Everyone, I... - Thyroid UK

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Changing from NDT to T3/T4 combo

Hi Everyone,

I have just received my latest results from Medichecks, and, although, they look pretty good, I still don't feel really well. I am beginning to wonder if Ndt is right for me. I previously tried 2grains but felt overmedicated. The Medichecks doctor issued the usual warning about suppressed TSH and Osteoporosis.

Results are on 1&3/4 grains

7 Nov 2017

Tsh - 0.127 (0.27 - 4.20)

FT4 - 10.6 (12.00 - 22.0)

FT3 - 5.81 (3.10 - 6.80)

I am thinking of doing a trial of T4/T3 combo just to see if I feel better than I do on NDT. I do have some T3 stashed and wondered what dosage I should start with. I was previously on T4 - 100mcg.

My Iron, Ferritin, B12 are all good and my Vit D is improving , I am currently taking 2000iu and will be tested shortly. Last result was 56nmols, up from 27nmols. I would be very grateful for any advice on switching.

Many Thanks


9 Replies

I would be inclined to give it a bit more time as it can take a few months for symptoms to reflect good blood results. Also what about doubling up on that vit d and taking 4000/ day as you are well off optimum still. Improving that could really help. Are you taking vit k2-mk7 and magnesium with that?



Thank you for replying, I have been on this current dose for about 2 months now and not sure that it is really working for me. I now have dry skin, swelling and a lot of headaches, which I have never really suffered from. These have only occurred since I have been on this dose. Maybe TSH is too low for me or maybe something in thyroid s doesn't agree with me. I have got a supply of thyroid from same supplier so maybe I will change to that and see if things improve. The Vit D result was from 6 months ago, and, I have increased dosage, it is to be tested again soon, so hopefully it will be better. Thanks again



Well ndt doesn't suit everyone. I don't know exact composition of thyroid s, but each grain of ndt is usually around 38mcg t4 + 7-9 (?) t3. So, depending on tablet sizes you have of t4 & t3, you could try and get as close as possible. Maybe 50-75 t4 + 10-12.5 t3? And then adjust from there.

But don't necessarily trust me, I am sure if you search for thyroid s contents or composition in search box, you would find numbers from those who know exactly what it contains!

Good luck.




2 months isn't much of a trial, especially as it will have taken time to get to a good dose. 1 and 3/4 grains appears to be the right dose as TSH is low but not suppressed and FT3 is in the upper third of range. FT4 is often low or below range when taking NDT or T4+T3 combination.

You could try alternative brands of NDT as not every brand suits everyone.

If you still want to try T4+T3 combination then an equivalent dose will be 75mcg Levothyroxine and 12.5mcg T3.


Hi Clutter

Thanks you for replying, I do have a supply of thiroid so I may try that and see how it goes. It is disappointing as I felt very well on Thyroid s to begin with. Many thanks again




Quite a few members have found that Thyroid-S doesn't suit but they do well on Thiroyd and vice verse.

1 like

Siddooo1, I agree with others that two months isn't a very long trial for a format of thyroid. I tend to think 6 months is a good time period. To my mind the goal of trying a format is to completely find out whether it suits you so that when you move onto something else you are pretty sure you'll never need to go back and try NDT again.

You do have space for a dose increase and are describing hypothyroid symptoms. You've tried 2grain, so why not try 1&7/8 to see if doing it more slowly helps. Or if you've had success on a different brand, try going to that? I'm just trying to suggest tweaks to make NDT work for you, as chopping and changing to a different format may mean you need to chop and change back to try some of these things in the future.


Hi, thanks for replying, I might well try taking 1&7/8, before trying anything else. I have been taking ndt since May 2017, and it is only since reaching my current dosage,that, these symptoms have shown up. Thanks again



That's interesting. If you've been on it since May that's more like a decent trial. When I saw the preview for this message I was going to say "if you haven't felt good on it since May, you've given it a good trial and it sounds a good idea to switch to something else".

But it sounds like you have been good on some doses? If you've felt better on lower doses you might try dropping back a little. The symptoms sound quite underdosed, but you can never really tell. You could drop back by a tiny increment and see if your sweet spot is between two doses you've tried before. The blood tests are only a rough guideline. Some people feel at their best at different points in the range.

Or are you in the state where you felt okay on lower doses but not close to 100%? This is a much harder judgement call to make :( You never really know how close to 100% any person will get to. Make sure you make very good notes about the best you've felt on NDT, just in case you need to compare it to where you are on T4/T3.


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