Thyroid UK
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Any ideas as to whats going on? - T3 only

Hello everyone

I posted a week or so back on my T3 regime - not going to plan. However, my latest increase of T3 6 days ago from 30mcg to 35mcg has sent me to a horrible place, aches and back pain, headachey and extremely irritable.

Have been off T4 for 3 weeks in the hope that rT3 was a problem but now i just feel like I am going backwards again. Initially dropping the T4 made me feel better.

Should I try to re-introduce the T4 or just get some NDT.

Any help would be appreciated, thanks


13 Replies

Have you ever had your rT3 measured? You may have had a small problem and it may already have cleared. In that case you might need a big drop in your T3.

However, it could just be that you were not suited to T4-only treatment, and you would do better on NDT. I hated T4-only and didn't feel well on it. I took to NDT from the first day I took it though - I felt so much better on it.


No I haven't been tested for rT3, I didn't feel good on the T4/T3 combo and someone suggested it could be a rT3 problem so I left the T4 out to see how it went. Small improvement to begin with but now after 3 weeks I feel absolutely awful again on T3 only, have only taken 10mcg today to see if the symptoms ease off.

I have ordered a trial of NDT, am ever hopeful it will work but if it doesn't I know i will have to dig a bit deeper into the more obscure deficiencies which i have not yet checked out.

Thanks for your reply, much appreciated and so glad to hear the NDT worked for you - I bet that is a wonderful feeling?



Hi Jan - I am on T3 only and find like you increasing between 30 - 40 range can be really difficult. One missing link for me is adrenal support. I have found taking 2 x Nutri Adrenal half an hour before the T3 dose is really helping. Also I have stopped NHS T3 as batches seem to make me ill. I am now on cynomel at 31.25 and am much better. ie 25 @ 4.30 am and 6.25@3.00pm if I get tired later I top up with Nutri Thyroid. One Nutri thyroid at bedtime seems to help with sleep. I wonder like you whether NDT should be my next trial. First I'm trying to work out any immune triggers I might have. Good luck working it out.


Hi Sarah

I had my adrenals checked out sometime ago and they are fine, just a little high at night but hopefully this has sorted itself out. I am on NHS T3 so perhaps that is where the problem lies - it kind of makes you laugh really, the medical profession go on about NDT not being consistent and here we have plenty of evidence that their T3 is far from perfect. Do you have to buy your Cynomel?

This has been going on for so long now I am running out of patience with trying different combo's and then T3 only to find I end up feeling worse.

If I try the NDT and it doesn't work then I will know that something else is amiss and i need to find the answer. Quite honestly you can spend a fortune on tests, there are just so many to check out and I have had all the obvious ones done - I am just going to consider my trial of NDT as another test, and if it works it will have been cheaper than having another batch of tests done.

Thanks for your help, much appreciated.


Just to say that I didn't gt on well with t3 . It seemed fine at first and I thought hey this is great. Then it all went off despite only being on a low dose combined with low levo. So I am back on plain levothyroxine we all work in our individual ways


Hi Jan - I am summoning courage again to question endo and GP re NHS lio.

I am trying to time it apart from my son's endo appointments so they don't link us. - Mad Mother Syndrome!

Having read Izabella Wentz book and thought more about the autoimmune aspect I wonder whether it is due to the packing / filling agents in NHS brand. - just a thought.

I am buying my cynomel from outside UK.

Like you am totally fed up with trialling and stop starting but wonder whether NDT is the missing link.

Have you sourced yours from UK?

Hope you have answers soon.


Just to add that I took cytomel first time round rom Italy. Second trial years later with liotir which is t3 in liquid drop form. Still felt ill


Hi Sarah

Sorry for the lateness in my reply, posted yesterday and it threw me off the site - weird. However, I sourced my NDT from outside the UK and hopefully it will turn up soon.

Do you have hashi's by the way? I wonder whether the body starts rejecting T4 - been on it for 11 years but things went badly wrong about 2 years ago, more T4 made me worse, had some relief from the T4/T3 combo but T3 on its own sent me to the madhouse - didn't think 35mcg was very much so didn't consider I was over-replaced.

Thanks for your support




The americans are starting to back off this idea of RT3 clearance, RT3 is a naturally occurring substance and most people do not need to go on T3 only to 'clear' it. Indeed pigs make RT3 so it's in NDT .... Personally not a big fan of the idea, think it's unnecessarily complicating what is in fact quite a simple process. Do you have any TFTs on T4 only?

Anyway, you said you adrenals are 'fine' but also that the test was some time ago and also you have a 'high' evening reading - that's not 'fine' that's 'abnormal' - what were your cortisol results and were you off all supplements that could interfere with a saliva test before you did it?

Also low iron can create funny toxic, hyper like symptoms. What are your iron results - ferritin, serum iron, transferrin, % saturation? T3 will set off all sorts of funny symptoms if the underlying 'ducks are not in a row'

T3 only is really hard on the body and it leaves nothing in reserve (that's why T4 is a storage hormone, so you can pull it out of storage when you need it). Synthetic T3 can be particularly harsh.

Also candida, low B12, low zinc, Vit D, low B vits, and out of whack electrolytes can create 'adrenal' or 'pseudo hyper' type symptoms. Gluten and leaky gut can be a big factor .....

I'm now on NDT and doing great but nothing worked for me until I'd sorted out the underlying issues. Also I had some bad advice to take progesterone BEFORE I'd sorted out my adrenals and thyroid and it was creating havoc (I have had a TT so my body does all sorts of funny things it shouldn't do, all bets are off on hormone conversion!) - people take all kinds of weird supplements thinking they will help - particularly adrenal type support and often that can be creating havoc. My view now is the bare minimum of supplements needed and no whacky herbal combos .....

My bet is it's your iron :-)

Best wishes



Hi Rebecca, thanks for your post.

I have read that the idea of rT3 clearance is a fallacy and yes I am aware that it is produced naturally by us and pigs, but for every person that thinks too much rT3 is a problem you get someone who thinks the opposite. It is one of the problems with trying to find your way through this nightmare - even the professionals can't agree.

I had been on T4 only for 10 years or so and T3 was introduced about 4 months ago gradually decreasing the T4 and increasing the T3 - my problems came 3 weeks after I dropped the T4 and tried to increase the T3 from 30 to 35mcg. I only ever made an increase after about 2 weeks, so didn't feel I was rushing it.

In July this year my iron was 20.2mmol/L (11-30), transferrin 117.1 (10-200) and transferrin saturation 37% - so i didn't feel that any of those might be causing me problems. As for my adrenals they were at the top of the range for morning 20.4 (12-22), then 6.8 (5.0-9.0) then 6.0 (3.0-7.0) and night was 4.0 (1.0-3.0), which I know is higher than it should be but I was advised that this could settle down and wouldn't cause me any problems - bad advise - maybe?

I have been tested for coeliac, D3, B12 and have hashi's. I do not take any supplements (herbal or otherwise) except for topping up my D3 for a few months (under endo's direction).

If I start NDT I will stay on it, I don't intend to chop and change. If it works that would be wonderful but if I run into problems I will then know I need to look at other issues and put them right.

Thanks so much, your help is much appreciated.



PS Also I've really had to learn to resist the temptation to keep jumping from one thyroid med to another. NOTHING will work if the underlying stuff isn't sorted - not T3, NDT, T3/T4 / T4 only. It takes really diligent, slow, methodical work - there are no quick fixes.....


Hi Which adrenal support are you talking about please which created havoc? I'm struggling at the moment and am interested in hearing people's experiences of it.


yes..not much better on t3 only, but had done it as a last resort. I have done levo/t3 combo and ndt, which flared up my hashimotos. The problem is that with hashimotos there is so much inflammation, your immune system is on fire, thinking your thyroid is a germ and it stays worked up..i believe some feel bad, as long as they are inflamed and have an autoimmune disease. fatigue and other symptoms are part of just having hashimotos or any autoimmune disease. We all have issues with food and leak y guts, whcih allow what we eat to effect our immune system. This is widely known, even on pubmed, which shows what was studied and published in mainstream medicine journals, for idiot doctors to read. All people with autoimmune disease have intestinal permeability. We need to find the root like the deleted post said..and find a way to get rid of it. Isabella Wentz, has her hashi's in remission. She had a flareup by using some makeup, regular stuff like we use every day. Once your gut leaks and immune system is bad, it is a balancing act for the rest of your life!! Unfortunately. But once you know your triggers, you do the same thing everyday and live your life...

if you are inflamed, t4 will not convert. Don't make the same mistake as i..redoing the same thing, like thyroid meds, over and over again, expecting a different result..i wasted is insanity. It is not the thyroid meds, especially if you are on t3 only. It is the only chance of getting it to work. Ndt is still mostly t4..don't convert, it won't work, plus the antibodies recognize it as a fresh thyroid to kill of..happened to me and greygoose, others too.

This is my opinion, based on trying everything and researching for 6 years, daily and loosing my mind doing so.

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