Can any of you lovely people shed some light on this question?
I have always taken bloods first thing in the morning 24 hours after last thyroid med dose. This was the case with Levo, NDT and now with T3. In this way I assume I am comparing like for like at all times to allow for reasonable comparison of response to treatment? When on NDT, my T3 levels were always above 3.5 (presumably reflecting what has been converted from the T4 plus the direct T3 inherent in NDT meds?)
Now I am exclusively on T3 meds, on a dose of 60mcg per day. I again had bloods taken at 24 hours, which showed a FT3 of 2.7.
The Endo says the T3 will have left the system by then and to test 4 hours after taking the dose. I am reluctant to do this as I fear it will show elevated levels of T3 in my blood.
My question is when should one take bloods when on T3 alone?
Also, why is my FT3 so low despite quite a healthy dose of 60mcg of T3 notwithstanding the short shelf life of T3? Why is it that I still remain tired and also felt poor heat tolerance despite not a very high FT3?
I must add that my adrenal function is now being investigated, but what impact could this have?
A million thanks to you all on this amazing forum for your pearls of wisdom!
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Sangrom
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My question is when should one take bloods when on T3 alone?
Approx 12 hours after last dose of T3. Alter time of meds the day before if necessary. No less than 8 hours, you'd get a false high FT3, no more than 12 hours as you'd get a false low FT3. You want the normal circulating hormone level which you will get if your blood draw is between 8-12 hours.
About half the liothyronine will have gone 24 hours later due to the 24 hour half-life. But the half life of liothyronine is very difficult to measure and probably varies between subjects. I would have the blood taken about half way between liothyronine doses this will give an approximation of average fT3 levels. Taking the blood four hours after taking the tablets will give a false high result.
60 mcg is very much a full replacement dose (although some people require more). This should be enough to raise your fT3 towards the top of its reference inteval. If fT3 is still low after getting the timing of the blood draw better then look into trying a different brand.
Thanks jiimh111- I take Thybon Henning, the German brand which is strong.. I cannot understand why my FT3 remains so low despite a full replacement dose and notwithstanding the 24 hour gap between doses..
I am starting to think maybe I do need T4 alongside..?
Thybon Henning is good quality. A quick calculation would suggest your fT3 would be about 3.8 if you had the blood taken after 12 hours.
I've assumed you take your liothyronine once daily. If so it would be better to take it twice daily for more even levels and by avoiding the high levels the elimination will be a little slower.
If you decide to split doses be mindful of finding a space in which your stomach is completely empty. This is from one of our Advisers (deceased) who was an expert on T3 and he also took it himself as did patient who had Fibro/CFS/thyroid hormone resistant.
Thanks shaws. This is precisely why I prefer to take it in one dose in the mornings on an empty stomach. I think splitting doses may just not work with my work life and I may end up inadvertently missing doses..
I shall give it a try and see how I get on. Thanks again
Besides we have a free life in that - when it relieves our symptoms- we carry on as we did before getting hypo and have no symptoms. It is a great feeling when we've been ill for a long time and being told - 'bloods are in range'.
Besides Dr Lowe only took one blood test altogether i.e. to diagnose a person - so did hi patients. Thereafter it was all about how their symptoms were relieved. He only prescribed NDT or T3 for his Resistant Patents and it was one daily dose. He said that those who were resistant only recovered with very high doses of T3 which would knock others off their feet. Of course it is always slow and steady.
Before blood tests we were diagnosed upon our clinical symptoms alone and given NDT until they resolved.
It's pretty easy to take a dose before breakfast and one at bedtime. I find the bedtime dose very effective presumably because the brain works hard at night. I take my morning dose three minutes before breakfast. L-T3 is rapidly absorbed unlike L-T4 so you don't need to leave a long time between dose and breakfast. You might want to leave more than three minutes to be on the safe side.
I would not take the chance of anything interfering with the uptake of T3 - that is because it has restored my life and removed symptoms through following Dr John Lowe an expert on T3 and as scientist to boot. He himself took one daily dose (as did his patients) but he took his in the middle of the night so that nothing at all could interere. Also by being hypo it also means our digestion is slow.
I would leave a lot more than 3 minutes, if I were you! We have seen people on here who take their T3 just before eating, and wonder why they're not absorbing it.
It will depend upon the person and the diet, especially if it includes much fat. I would leave an hour to be safe and then experiment with a shorter period if you want. I usually have porridge with semi-skimmed milk and orange juice which probably doesn't challenge the absorption as much as a heavy meal. Avoid coffee with thyroid meds.
You might well not be absorbing T3 as effectively as you think. May also interfere with the uptake of T3 and maybe take more due to that. I am sure Dr Lowe, scientist/researcher, had researched well. He, himself, took his in the middle of the night so that nothing whatsoever interfered with the uptake of his dose of T3. All of his patients allowed a reasonable gap between dose and food. Why would very sick and unwell people not give their body the best possible outcome.
Blood test results show absorption is good. Liothyronine is easily absorbed, usually 95% whereas levothyroxine absorption is poor, around 60% depending on the individual. There's a big difference between the two.
I am aware of what Dr L took that's why he was such a good doctor. He didn't have hypo but Thyroid Hormone Resistance which seems to be unknown in the medical profession:
"Deciding if a Patient is Resistant to Thyroid Hormone. Resistance to thyroid hormone is a relatively new but well-researchedfield.
[1,pp.295-338]
Researchers first documented a family whose cells are partly resistant to thyroid hormone in 1967.[221]
In 1990, other researchers found one cause of the resistance: a mutation in a gene on chromosome 3.[220]
More than a hundred mutations have now been found in this gene in different patients who are resistant to thyroid hormone.
.....
During the trial, the patient carefully progresses through metabolic rehab using plain T3. The method of adjusting her dose of T3,and the safety monitoring she undergoes, are based on our experiences with hundreds of resistance patients and our scientific studies of those patients.
[36][38][92][93][94][
135][137][188][189][292][403]
We want to emphasize that our patients use plain T3—not sustained-release or timed-release T3.
They take their full dose of T3 on an empty stomach (one hour before a meal, or three hours after)once each day (see Figure 1).
I had RTH and wanted to discuss it with him but he unfortunately had his accident at the time. His patients have a very severe form which I believe is caused by hormone disruption. In these cases the dynamics are a bit different, in general sustained release T3 would be ideal. I've no problem with people leaving an hour before having food. I was on up to 120 mcg L-T3 a day but found no difference in having food a little while after my tablets. We used to recommend taking L-T3 with food for slower absorption about a decade ago. I'm not in any way opposed to leaving the hour gap just mentioning that if it is a problem for some people they can try a much smaller gap.
I know, he was treating a specific group of patients. Since then our understanding of RTH and deiodinase has moved on. Also the human burden of endocrine disrupting chemicals (EDCs) is slowly declining, we should see fewer patients with his severe form of hypothyroidism, they tended to be in the USA where EDCs are an order of magnitude higher.
I have the DIO1 mutation- but when I told the NHS consultant Endo this, he said there was no evidence this affects conversion and warrants administration of T3 meds...
DIO1 polymorphisms can affect T3 levels a little but they don't seem to affect symptoms. You might need some T3 but the polymorphism most likely has nothing to do with it.
Thanks jiimh111- Interesting- I have been put exclusively on T3 based on the DIO1 finding- but am not responding as well as what I would have hoped and hypo symptoms remain. I did v well on NDT (Naturethroid), but found that I had to keep increasing the dose to maintain an elevated FT3 level. Every time my FT3 drops to below 5, I get hypo symptoms and bad hair loss. It got to the point that I was on 5.5 grains and FT3 levels did not stay above 4.6- with persistent low mood, hair loss, water retention etc etc. Any ideas?? I am so desperate to get this sorted and reclaim my health and vitality.. Thanks so much
It could be poor absorption but unlikely unless you are on a very strict diet or have gastrointestinal problems. I would switch to twice daily dosing as it will give more stable levels which are easier to measure. More importantly I have found the nighttime dose to be most beneficial, it help clear the mind and I feel more refreshed the following day. I believe you currently take your liothyronine in the morning, if you clear it out rapidly you will have low levels overnight. This could in part explain your poor response so far.
Thanks jiimh111- what had perplexed me though is that I have felt v overheated at night, by which point the T3 I had taken early morning should have cleared...
I don't understand this as your fT3 is low. I can only guess it is due to another reason. If you start taking half your liothyronine at night you can see if it makes a difference.
Reading through this post the symptoms of anxiety & low energy could resolve by splitting your dose. 60 is a lot in one go. T3 acts so quickly it could be you are experiencing hyperthyroid symptoms. I would take your blood test as suggested above, but think maybe give it a couple of weeks for your body to settle into the new dosing regime if you can. Split dosing is a pain, I make sure I have not eaten 2 hours prior and have only water for the following hour then take my second dose. Easy for me as I am trying to lose weight.
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