Thyroid UK
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Problem solved - Do need T4 - I think! Optimal T4/t3 ratio?

Hey guys

Having been baffled by my continuing health problems and new symptoms and having tried everything, I just clicked and think I know what is was and thought I would tell you in case anyone else has similar difficulties.

For the last year, I've had increasing problems with my brain (memory, maths, thinking), massive hair loss, no energy or sex drive and increasing hyperthyroid symptoms including nausea, shakes, hyper reflexes etc etc

My thyroid started failing over twenty years ago and have been on T3 only for nearly 15 years as T4 never worked and couldn't convert. I remained on T3 only until I became pregnant in 2010 when I added a tiny bit of T4 as not clear if the baby required some and wanted to play it safe. I stayed on T4 out of habit for some time after I gave birth but I had also stopped smoking again and my already terrible health managed to get even worse and was going diabetic and my adrenals started failing etc.

I then gave up gluten as a last ditch attempt and many of my lifelong illnesses disappeared (sleep disorders, water retention, pompholyx, stomach issues, etc etc). Some of my deficiencies such as iron did improve to some degree also but still require meds and my sugar levels stabilised plus the skin pigmentation caused by adrenals went away again. I felt so alive and the best I had done since a child and I also quickly became hyper and dropped the T4 first as never had much use for it and then dropped the T3 from 60 to 40. I was a little up and down over the next two years as I had many gluten trials for testing so it was hard to say where I was as always took months for levels to normalise after the gluten trial and then would have to start another one.

Anyway, after these were completed, I was hoping to finally get back to where I was the first year I went Gluten free but it wasn't happening and started with the symptoms I mentioned above. I literally thought I was losing my mind and becoming stupid. Even though my T3 levels were above range, my tsh was still raised which wasn't making much sense. Because of the hyper symptoms, they have run my thyroid low since october and although the hyper symptoms dissipated such as the nausea, I became hypothyroid and basically couldn't win and the brain/hair problems never improved.

Since October, I tried everything else to see if made difference - B12, vit d, iron (still remains low) etc etc but nothing did. I then got some T4 last week on the hunch that there's no other option if I can't take more T3 and maybe I can convert now since the removal of what was always the problem (gluten) and show no inflammation in my system since going GF.

My memory has improved a little since last week as am not dropping info so quickly and I feel a little more balanced but it will be a while to know for sure I expect.

However, last week, I decided to call the surgery and look at some of my old blood tests and it appears that up until I got pregnant, I was in fact making a little T4 of my own - around 3-4 in a range of 7-20 and obviously I was taking the extra T4 from pregnancy up until some months after I gave up gluten. All my blood tests since then have shown no T4 at all even with tsh raised to 30-50 so it appears at some point between giving birth and going GF, my thyroid finally gave up the ghost so have had no T4 in my system since dropping the bit I took for pregnancy - maybe when I quit smoking again. I think this is definitely the issue as it all makes sense time wise and would explain why my tsh continues to be raised even when T3 well over range. So possibly just some extra evidence you can only have T3 only if you are still making some T4 yourself???

I'm hoping this will resolve my issues now and am feeling a little more optimistic but many thanks to HIFL for suggesting this to be the case in the first place (I don't know how to tag her).


Edit - meant to ask, If it turns out to be case and I can utilise T4 now, does anyone have any clue how much T4 I might need?

8 Replies

SaggyUK to tag a member

Adding T4 should bring down your TSH but will probably raise your FT3 too. If your FT3 is over range consider dropping 10mcg T3 for every 25mcg T4 you add.


Hi Clutter, I will edit and tag them, thanks :-)

They've been running me low for months as this was preferable to the hyper symptoms and my last results were:

tsh - 10.18 (0.35-5.0)

T3 - 4.5 (3.8-6.7)

So t3 is low at the mo so we have just added 25mcg of levo for now. I suppose just wait until the next blood test in July and see what changes. :-)


A good way of using T4 with T3 is to just try using the lowest amount which is really a 25 mcg tablet. You then hold this level and try and adjust the T3 to balance you up.

It is hard to say what level of T3 you will need, but for me the maximum amount of T3 i could use was 55mcg. I took this when i was doing 25 T4 and 55 T3. Over time i wanted to see if i could use more T4 and less T3 and over two yrs went from that mix to 125 T4 and pretty much no T3.

Before i did this i was on 150 T4 and 50 T3 and still not well. So i decided to go for mostly T3 and a little T4.

I think taking less T4 and more T3 allowed the body to use the hormones more effectively and when i adjusted slowly the changes were accepted by the body.

I do convert well though, so this may not be the same for poor converters.


Hi marsaday, Thanks, yes before when thyroid was stable with tsh just under one, I was always on 60mcg T3 and no T4 but it has been proven in the gluten trials that I need less thyroid replacement when not eating gluten which is why I had been on 40 since, just couldn't stay on the 40 recently as mentioned and have had to run low on 30mcg. I have added the 25mcg levo as you mention so will see what happens with my symptoms and levels with the next blood test :-)


Sounds good. If you hold the 25 T4 and then mess with the T3 level this means you will know what is doing what to the body. Over time you could then move up to 50 T4 if all is ok and see how that goes.

If you change the T3 level, then a few days later change the T4 it is really hard to work out what has done what. So i tried to hold a steady amount of T4 for months and in that time change the T3. Once settled i held and then tried a T4 increase. Each period of time was at least 3 months. So it took a while to change over from T3 to T4. I am not saying you need to do this because T3 sounds like it is good for you, but it shows you how you can change the doses around and how long it takes.

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Thanks, yes that does make sense to only change one thing at a time even though will take longer lol so will do as you suggest. We always leave it three months min to see how changes effect me as always takes that long for me.

THanks again :-D

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When I reduced levo and increased t3 (to deal w rt3) it really messed w my head/memory. When I added in a bit more levo the improvement was immediate. Like you I'm trying to find the best ratio and I know there are guidelines but irl it seems like you need to experiment a little and find what works best for you.


Yes, I see now that it will just have to be trial and error and it's not going to be the same for everyone so will do so. I suppose the best place to start maybe to try and get my T4 levels to where they were before when I was producing a littleT4 on my own (4-5) when thyroid results were stable and tsh was just onder one. I might get copies of all my results back then to see if any further clues. THanks puncturedbicycle :-)


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