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?