Ok, so as the title suggests I’ve been on T3 only now for a few weeks having had little luck with T4 and combination treatment. I’m currently taking 120mcg T3 per day, split into three doses.
One of the main reasons my doctor and I agreed this approach was my sky high RT3 result which I’ll come onto in a second, as I know this is controversial
Here are my latest results:
TSH: 0.02 [0.27 - 4.2]
FT4 - 3.27 [12 - 22]
FT3 - 8.83 [3.2 - 6.8]
I the observations are fairly obvious. TSH and subsequently FT4 are significantly suppressed (but not quite eliminated), and FT3 is now well above range, to the point where you might argue I am over-medicated.
That much may be true, but the reality is that at this moment in time I feel utterly hypothyroid; absolutely no better than I did at the very beginning. I don’t have a single symptom of hyperthyroidism, no matter what my bloods suggest.
In my head, this backs up the high RT3 result and the lack of response to T4. I know that RT3 isn’t a direct inhibitor of cellular T3, but it seems that it is at least a marker of such an issue taking place.
That’s what it feels like to me; that my cells simply aren’t benefiting from the high FT3 levels I have circulating. I am just hoping that in a few weeks, having eliminated T4 and it’s substrates from my blood stream that I begin to feel the positive effects I am begging for (and I realise at this point I may need to dial down the dosage).
Any thoughts on this? It would make a lot of sense to me based on what I’ve experienced to date, however I will bow to your much greater knowledge.
Thanks!
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JonnyA
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JonnyA Only thing I would say is don't expect hyper symptoms to be any different from hypo symptoms. In my experience forget about those nice lists you read on the internet, clearly identifying what is hyperthyroid and hyperthyroid = in real life it is not clear cut.I was very hyperthyroid, had RAI and quickly became very hypothyroid so I have experienced both....and my symptoms were identical.
120mcg liothyronine? Assuming that isn’t a typo? That’s going some, in 8 weeks. Not a criticism, just an observation. Some do need high doses. But usually people take a lot longer to arrive at those doses…
How long a gap did you leave between taking your liothyronine and doing a thyroid blood test?
That’s what my endocrinologist prescribed. It may be worth noting that I’m taking no T4, and that this is an intentionally T4-suppressive dose of T3, so all my T3 is now coming extraneously.
I take my last dose around 6pm, and my blood test was at 9am the following morning, so that’s a 15 hour gap which I presume is sufficient for testing purposes?
I think we’d say that 15 hours is on the longer side—12 hours is better. So it’s likely your FT3 would have been slightly higher with a bit less of a gap.
Even so, your FT3 is surprisingly low for that amount of T3 going in.
Makes me wonder whether part of what’s going on has something do with gut absorption issues. Do you have any obvious gut issues?
Alternatively, you might suddenly find that 120mcg T3 hits you like a ton of bricks. I’m relieved to note you have an Endo monitoring the situation.
What specifically should I look out for in terms of this figurative ton of bricks?
Right now I feel exhausted, thick brain fog, need huge amounts of sleep, can’t lose weight no matter what. All the classic calling cards of hypo.
Presumably, if nothing else, this kind of dosage not having had any noticeable effect on me would reaffirm that my issue is definitively thyroid related? I’ve had one or two doubts in my darkest moments, but presumably a euthyroid person on this kind of dosage would notice some pretty strong effects quite quickly, right?
I think you’d notice. Racing heartbeat, feeling wired, feeling shaky etc. Loose bowels… Sounds like at the moment you’re experiencing the opposite.
I wonder actually whether the whole RT3 thing is a red herring and you have a case of resistance to thyroid hormones at a cellular level. In which case, you’re still doing the right thing in taking T3 only. Personally I’d just be a bit nervous of taking double the usual replacement dosage of T3–but in those with resistance it can sometimes be what’s needed.
You didn’t answer my question about gut absorption—any noticeable gut issues? Because that would be the other reason for not absorbing as much T3 as one might expect.
Just checked my heart rate on my phone and it was 48bpm, which is fairly typical for me. Oh, and I’d give anything for loose bowels - not to be crude but you wouldn’t believe how constipated I am.
Out of interest, what would cause resistance to thyroid hormone at the cellular level? I tested RT3 because I lost a lot of weight a few years ago - probably about a third of my body weight. I was very lean, about 8-10% body fat at one point, and that’s when all the problems started.
I probably did engage in too high a calorie deficit at the time through a combination of diet and training.
In my mind I imagine a situation where I gradually start to feel better (hopefully), and then perhaps feel slightly hyper at which point I’ll reduce my dose. Could it creep up on me quicker than that?
Sorry I missed your question about gut health. Other than the consolation I mentioned above, I’m ok as far as I’m aware. No noticeable discomfort, though I’ve admittedly not had my microbiota tested.
One way or another I’m hoping this hell is over in the next few weeks. It’s driven me to the brink of suicide and though I feel in a better place mentally right now, I’m physically shattered.
Having high rT3 with such a low level of FT4 tells you that the high rT3 has nothing to do with the thyroid. There are many, many causes of high rT3, not just thyroid problems. So, presumably, there is something else going on that is causing it. Low-calorie diets are one cause. Are you eating well?
Also, a guide to gut health is the levels of your nutrients. Have you have vit D, vit B12, folate and ferritin tested?
OK, so you haven't had it tested since going T3 only. Well, if the cause was high FT4, it's had plenty of time to drop in 8 weeks. rT3 only stays in the system for about 2 hours, and is then converted to T2. So, if you were going to feel any benefit from lowering it, you would have felt it by now.
If your nutrients are good - without supplements, or course - then your absorption from the gut shouldn't be the problem, either.
Regards the notion of RT3 only staying in the system for circa 2 hours, is this undisputed, medical fact? I’d genuinely appreciate seeing a few consistent sources on this, as everything I’ve seen seems contradictory and if I’m barking up the wrong tree I’d like to know ASAP.
However, as has been said above, if your problem is absorption at a cellular level, you are doing the right thing by taking high doses of T3 only. That was my problem, and at one point I was taking 225 mcg T3 daily and still feeling hypo.
Thanks. May I ask if you ever reached a conclusion in terms of what was preventing cellular absorption, and at what point you found relief from your hypo symptoms?
I have no experience of medicating T3- only and these large doses, but would say (as previously) elevated RT3 is certainly an almost direct inhibitor of good cellular T3 uptake. Deiodinase type 3 is the enzyme that rises to dominate in states of severe illness and/or excess T4, and/or excess T3.
Now theoretically RT3 should clear once T4 has washed out of your system but remember that D3 can also become up-regulated by elevated T3 (and not just elevated/unusable T4) which would result in conversion of T3 to inactive T2. This would account for the high dose of T3 you are medicating that is not wholly reflective in your labs.
You might have missed your sweet spot, so needing to reduce T3 levels. Did you read the link I gave you last post regarding Tania Smiths explanation of D3 up-regulation?
O to 120mcg T3 in 8 weeks is far too fastRocket fuel in an old Mini!!
Your body is possibly confused by rapid change.
I need high dose T3-only to function
Has been 212.5mcg....now 100mcg.
I was eventually overdosed on T3 ....I assume some inactive T3 receptors wakened up!
Jittery, losing too much weight etc...you will know the list!
I don't do blood tests on that dose.....TSH suppressed, FT suppressed and FT3 over range would be the result
I use the old fashioned way.....signs and symptoms.
Resting heart rate, basal temp, the tremor test
You may be suffering the converse effect of T3....I.e. overmedication can feel like undermedication
I prefer not to use hyper and hypo ....misleading terms for over and under medication.
Your RT3 isn't connected to thyroid ...T4 would need to be high.
Do you exercise heavily?
To reduce I cut right back to 50mcg for a few days and slowly increased again till I improved.
But we are all different and others may suggest other ideas.
Being cautious I might first drop to 100mcg
Just a few thoughts
PS JonnyA
This might help....but in your shoes and after the rapid increase I'd still reduce and build up again because it's also possible you may have missed your dose sweet spot
I have no definite idea as to why I have low cellular T3 though suspect, based on my medical/ family history that it is genetic and that I've had it all my life. As the years passed my cellular T3 level appears to have changed from just ticking over to struggling to function. I asked a geneticist ( another long story) if there could be a genetic link with a known rare deletion. His response was that " we just don't know"... there could exist an as yet undiscovered genetic variant. So...it's not all black and white!
I had no idea why I had so many health issues (that medics could not satisfactorily explain) I had numerous tests, scans and treatments both NHS and private but I still had numerous, and increasing, issues. Mainly pain, weight gain, exhaustion and brain fog....to crumbling nails and gastro issues! I was convinced that an answer existed and knew it was up to me to find it....long story....but after time I did. I had to self diagnose and self medicate.
It can be a long, bumpy, frustrating, depressing lonely journey, accept this and focus on seeing the light at the end of the road. You will crash if you exceed your body's speed limit!!
I'm now 76....I wish the internet had existed 50 years ago!!
You have youth and modern technology on your side...and this amazing forum.
Thanks for that Dippy, it’s certainly not been an easy ride so far so I feel your pain. I’m hoping and praying that finally, I might just be closing in on the answer, and a solution.
As it stands, I’m still suffering fatigue, still struggling with weight, still have a slow heart rate and so the idea of me having overstepped the mark may well be right, but doesn’t ‘feel’ that way.
I think I may give it a couple more weeks on this dose and then try reducing.
Thanks for all your words of advice, and sharing your experience. All the best.
DippyDame you are saying what many of us are thinking. I know I'm one of them. I too wish the internet had existed 50 years ago!! I feel so Blessed with having this forum and all the wonderful members. It would be nice if we could have one day Zoom Meetings .
When my T3 was too high and my TSH very low, I was surprised to find that I felt a worsening of all hypothyroid symptoms. I thought I would have symptoms different from being hypo., but like one of the posts said, that isn't the case.
The last link provided explained how too high levels of both thyroid hormones can get converted to inactive forms, ie iodination to T2 (both forms).
In this article Tania Smith explains T4 & T3 metabolites & pathways, and how no matter how high we take total T3 levels, even good FT3 levels are not a guarantee to achieve well-being as may not address/correct the underlying problem of unbalanced metabolic losses.
Not all T3 will make it to the transportation stage into cells, metabolised within the cells, or to achieve signalling activity because of the many non-deiodination losses, including T3 sulfate, glucuronate, Triac, and urinary loss that both circulating and intracellular levels may suffer.
It took a while for the high reverse T3 to get out of my system. (At the time, I was taken off levo and put on amour thyroid). I also think that when your endo put you on such a high dose to start with, you could have missed your sweet spot. Maybe they made a mistake? It might be worth asking. As too much medication can have the same effect as not enough. When I had too much reverse T3, I was on a very low carb/low calorie diet under 50 carbs/1200 calories a day as I was terrified at gaining more weight as I was over 16 stone at time. My nutrionist talked me into adding more fruits, veggies and good fats to my diet along with berries avacados in my clean whey protein daily shake and asked me not to count calories or carbs. She also had me take pro-biotoics and digestive enzymes, in addition to the thyroid suppliments. Thankfully, I didn't gain any more weight, but it took quite sometime b4 I started losing some. It might be worthwhile seeing a nutritonal therapist to get their take on your digestive system and an ideal eating plan that would work for you. I had to do allergy and food sensitives tests for her, so she could tweak my diet properly and it was worth it! I hope you start feeling better soon.
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Racing heartbeat, feeling wired, feeling shaky etc. Loose bowels… Sounds like at the moment you’re experiencing the opposite. 
Answer to the High T3 question?
On combined t3/t4. FT4 and FT3 at bottom or out of range but increasing the dosage is barely raising the blood test results, TSH suppressed
Rt3 “high”?
Size of Thyroid and T3 Levels
