I have a question for you knowledgeable folk out there. I have tried to find an explanation alternatively but I would very much prefer to see what everyone says.
If t4 is the inactive hormone then why do you know when you increase your dose?
I upped my dose of t4 and definitely knew about it for a few weeks and now 12 weeks later my level of this hormone has raised by 22% through the range to 52% However my t3 has raised by 0.54% to 33% . My tsh is at 0.29.
Does this mean:
A) tsh does have a physical effect? I doubt this as I literally feel no different to how I felt before the increase now.
B) t4 does have a physical effect even though it’s classed as inactive? Maybe I am misunderstanding what inactive actually means?
C) the increase does boost the t3 initially but once your body gets wise to it it will drop off again? This would seem odd as if you aren’t converting surely it wouldn’t do it even in the beginning.
Confused and have emailed endo so just trying to get my head straight as have have asked for some t3 and want to know my stuff if possible.
Thank you x.
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Yeswithasmile
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Taking in order:T4 is not totally inactive but its main role is to act as a less active precursor substance, which is converted to T3 by the tissues outside the thyroid. This T3 is the active hormone (it has lost one iodine atom compared to T4). The reason why the thyroid makes T4 or you take it is so that it can been transported to the place it is needed for conversion to T3 without badly affecting other tissues it encounters on its way. This way you get local reaction to a local T4-T3 conversion.
TSH is only a marker to show the level of thyroid hormone in the body. It doesn't have a large direct effect outside its stimulation of the thyroid gland but should be thought of as a marker.
T4 probably has some effects itself but they are small compared with T3.
Increasing your T4 will increase the resulting T3 and lower the TSH and this will stay more or less the same as long as you take a steady dose of T4. Increasing the T4 should lower your TSH and raise T3, and vice versa if you lower the dose.
Ok. Thank you for your answer. It helps although even if t4 is minimally active is that what creates the initial symptom do you think? In a case where the t4 hardly has any effect on the t3?
It’s just strange to get symptoms within a couple of weeks of an increase and then when that subsides the active hormone hasn’t really raised, you don’t feel any better even though your t4 has then improved.
I’m also assuming that taking t4 which in turn lowers tsh would mean absorption issues are unlikely? And that the little effect on t3 is more a poor conversion issue.
I have been doing vits now for 4 weeks. I have the better you vit d3 with k2. I have the ingennus b complex and b12 lozenges. I have bought magnesium gylcinate and selenium but haven’t started this yet and have been looking at vit a too.
I’m trying with ferritin but until I had my hospital tests (just had and included fbc) I Didn’t want to go over board as my iron stores were ok etc and I didn’t want to over do it so I have done the liver pâté but only once a week. I had it all this checked this blood test and they are all only minimally raised but I thought it was early days still.
I also thought - maybe naively- that the poor t3 raise from upping my levo couldn’t just be from low vitamins etc which is why I thought I’d email the endo and see what he says about my request for t3??
As for the hyper mobility ... interesting. I can say that although I need to work on everything the t4 has been a godsend for me. I still have the pain and joints slip but I can say I rarely lay in bed unable to move now asking for someone to put me out of my misery! It’s been massive for me and I have explained this to the endo this time along the lines of don’t keep asking if I want to be referred to yet another rheumatologist, just give me some t3 to try. I am improved 👏🏻 but I know I could be even better. 🤞🏻🤞🏻
I hope that you're good and surviving this latest lockdown ok? x.
There does seem to be a difference in experience with the alternative types of t3 occurring meds though doesn’t there? Some people do well on ndt and some better on t4 and t3?
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ATA document on Thyroid Hormone Treatment
The role of T4?
How much should my liothyronine be bumped up?
TSH is just the 'opinion' of your Pituitary about your dose ~ but your Pituitary's 'opinion' is a bit warped once you take Thyroid Hormone.
End of the road?
