I have been on NDT since June of 2021. I am currently taking 175mg of compounded thyroid. About two hours after taking my thyroid capsule I often feel hot and sometimes a bit anxious ( like being overmedicated) but in the afternoon I am out of gas.
My cortisol is high in the early morning, good in mid morning, low in the afternoon, and good at bedtime. Iron, VitD, B12 all looking good.
No matter what we increase to, I can never get my FT4 above 0.9 (range 0.8 - 1.8) and my FT3 always hovers around 2.9 (range 2.3 - 4.2). That said, my antibodies do keep coming down and are at 199 right now. TSH is at .24.
I have spent the last several months working on gut health and adrenals. I am considering trying T4 only as I wonder if the T3 spike in the morning is throwing me off. Right now, I do not want to try to split my thyroid dose throughout the day.
I was hoping someone could explain the T3 feedback loop. I have had a difficult time trying to research.
Any feedback would be appreciated.
Kind regards.
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BlueGreenHealer
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I'm really not sure what you mean by the 'T3 feedback loop'. The only feedback loop I know of is when the hypothalamus senses that there's not enough thyroid hormone in the blood, instructs the pituitary to make more TSH and the extra TSH stimulates the thyroid to make more thyroid hormone. But, that involves both T4 and T3 - although, admittedly, T3 has a great influence on this loop than T4 and therefore the TSH is much lower when taking T3 than on T4 mono-therapy. But, as I explained to you on your first post, when you are taking exogenous hormone, that loop is no-longer reliable.
Also, taking T3 is going to lower your FT4. That's just what it does. And this is ok for a lot of people. Those who need their FT4 higher often take levo with thier NDT. But, I would say you just need an increase in NDT because both are too low.
Antibodies have nothing to do with anything. They are just an indication that you have autoimmune thyroiditis - aka Hashi's. The do not cause symptoms, they do not attack your thyroid, and even if you managed to get rid of them completely - highly unlikely - you would still have Hashi's because that doesn't go away. Antibodies fluctuate all the time, it doesn't mean anything.
I am considering trying T4 only as I wonder if the T3 spike in the morning is throwing me off.
I cannot imagine that that would do much good to either you or your adrenals. Not now your body has got used to having the T3. But what do you mean by 'throwing you off'? If you don't want to start splitting your dose now - although that might be the solution, and would certainly soften the spike - how about trying taking your hormone before bed. That suits a lot of people very well.
My understanding was that once direct T3 is added to therapy, our thyroid no longer produces T3 on its own. That a negative feedback loop is created and so the correct dosage must be found for the patient. So I guess I am just trying to puzzle out if that is true?
I think I am just frustrated that after three years, I still cannot get this sorted.
In 2021, my TSH was a little high at 5.6, but my FT4 and FT3 test results were actually better (not optimal, but definitely better) prior to beginning thyroid hormone. My FT4 was 1.1 (range 0.8 - 1.8) and my FT3 was 3.3 (range 2.3 - 4.2). I wish I had known more at that time about adrenal health, because I think that needed to be the first focus and wait to treat the thyroid..
When I say "throwing me off" I mean that I think the T3 dose in the morning is too much and then there isn't enough left in the afternoon to keep things running smoothly. I think this puts stress on my adrenals. I was considering T4 only because I simply do not have the bandwidth at the moment to worry about splitting the dose. I have tried taking it at night and I don't sleep. Based on my test before beginning thyroid hormone, I do not seem to have a conversion issue; I was doing pretty well making T3 on my own (even with poor gut health and wonky blood sugar due to poor dietary habits - at the time). So I wondered about taking T4 only and trusting my body to do its own thing. 🙂
Ah ok! I see what you're getting at. But it's not just T3. Even when you start levo (T4), the TSH starts to drop and eventually drops to a level where the thyroid becomes unable to make any hormone at all - neither T3 nor T4 - so that eventually, you are entirely dependand on exogenous hormone - well, more or less. Impossible to know if the thyroid does continue to make tiny doses of hormone or just goes quietly to sleep.
That is why we have to start on low doses and increase slowly, so that the change-over happens slowly and smoothly, and the body has time to adjust. But yes, we do have to titrate slowly until we get to the right dose for us. That's not exactly a feed-back loop, just a gradual progression from hypo to euthyroid.
So, before treatment:
FT4: 1.1 pmol/l (Range 0.8 - 1.8) 30.00%
FT3: 3.3 pmol/l (Range 2.3 - 4.2) 52.63%
Your FT3 was higher than your FT4, which is a sure sign of a failing thyroid. But your thyroid could not have maintained that level of production eternally. At some point, the FT3 level was going to start falling no matter what the TSH level.
And now your results are around:
FT4: 0.9 pmol/l (Range 0.8 - 1.8) 10.00%
FT3: 2.9 pmol/l (Range 2.3 - 4.2) 31.58%
So, your FT3 has dropped a lot, indicating serious under-medication. But not sure that has anything to do with the adrenals. When T3 levels start to rise, the adrenals often just sort themselves out.
When I say "throwing me off" I mean that I think the T3 dose in the morning is too much and then there isn't enough left in the afternoon to keep things running smoothly.
No, that's not how it works. T3 has a half-life of about 24 hours in the blood. That means that, if you take 10 mcg at 8 am one day, by 8 am the next day, there is about 5 mcg left, minus what got into the cells. But it is not active in the blood, it doesn't do anything. It has to get into the cells to become active. And the T3 that gets into the cells stays there for about three days. So, if you're taking T3 every morning, it doesn't - it can't - run out. That's not to say that you're not under-medicated, but what you're taking will always be there, all day, every day.
I think this puts stress on my adrenals.
What's putting stress on your adrenals is being so under-medicated.
I was considering T4 only because I simply do not have the bandwidth at the moment to worry about splitting the dose.
Which would put even more stress on your adrenals because they've got used to having the T3, and you'll have even less if you stop taking it. That really does not sound like a good plan to me.
Based on my test before beginning thyroid hormone, I do not seem to have a conversion issue; I was doing pretty well making T3 on my own (even with poor gut health and wonky blood sugar due to poor dietary habits - at the time).
You cannot draw any conclusions from those labs before treatment because they were done on a failing gland. And a failing gland does not behave like a healthy one, as I explained above. The T3 in that test did not come from conversion, it was made by the gland itself. If you are still taking T4, the gland will not be making any hormone, T3 or T4. I'm afraid your whole understanding of how this works is faulty. The days when your body could do its own thing are over. You are hypo and everything changes. You have to adjust.
What you need to do is keep titrating your dose up until you feel well.
I have tried to educate myself, but there is so much conflicting information and so many opinions. Like I said in another response, even my ND says things that don't line up with the information provided here.
Do you happen to know anything about slow release T3? I am going to search it here too. I am in the US and have my medication compounded. Luckily, doing this is not too much more expensive than if I used insurance for Armor. So I wonder about Taking T4 and adding both direct and slow release T3? Maybe then I would not have to split the dose?
The problem with slow release is that it's uncontrollable. You never really know how much your going to absorb. And if you have an attack of the trots you probably won't absorb anything at all! We see lots of people try it on here, but not a high success rate.
So, I really don't think taking it is a reliable substitute for splitting the dose.
That said, I've never tried it myself, and have no desire to. I just don't trust it.
Where doctors are concerned, I don't think it's so much a problem of conflicting information, I think it's more a total lack of information. They just don't know that much about thyroid. And I often have the impression that they just make it up as they go along. So, I'm not surprised that what he tells you conflicts with what you read on here. But, personally, I would trust what's said on here more than any doctor.
The ‘T3 feedback loop’ is situated within the HPT axis (hypothalamus-pituitary-thyroid). These three glands produce hormones that either encourage more or less thyroid hormone depending upon needs. Once we medicate thyroid hormone replacement meds we aren’t reliant upon the axis sensitivities, which appear to change anyway and many consider the feedback loop to be broken.
Labs are useful when raising meds but aren’t always a good indicator of long term levels if FT3:FT4 ratio is incorrect. This is because the body’s protective mechanisms will convert over-medication to inactive metabolites, and when this happens the conversion enzyme (D3) reduces both T4 & T3 congruently, even if only T3 is the problem.
NDT is a great med (I take it) but the T4:T3 ratios are fixed and don’t suit everyone. As both your levels are low but you are unable to raise it might be prudent to assume there is too much T3 within NDT for your specific need. This is when reducing NDT dose and adding some Levothyroxine is beneficial and what I needed to do.
You don’t need to split NDT as the hormones are still bound to thyroglobulin. This acts as a natural ‘time release’ mechanism. More info here …… healthunlocked.com/thyroidu...
Thyroid meds that aren’t suiting will stress the adrenals as will unbalanced sex hormones. You have also detoxed mould (which I have done) and it’s a long, slow process that can exert much influence on how your body is working.
Its great thyroid antibodies are reducing. They induce unwanted chronic inflammation and contrary to thought on the forum TPOAb does attack thyroid tissue, so intensifies Hashi attacks that become self driving.
I have seen a study which showed NDT had similar pharmacokinetics to liothyronine, T3 was released into the blood at a similar rate. I will try to find it. The hypothesis that hormone bound to thyroglobulin is released more slowly is reasonable but it doesn't appear to be so.
There are further references within the link in my reply to O/P, but I would be equally interested to read the study you found because some members say they feel better multi-dosing NDT.
I've had a look for the study but can't find it. When I come across it I will post on the forum. For now all I can say is I'm pretty sure I saw a study showing T3 variations similar to liothyronine. I remember researching the stuff diogenes posted but couldn't find a study. It seems strange that they sat the time to peak for T3 is longer than T4, so I suspect this information has errors.
Thank you for this! I have read and re-read your response and this is definitely what I was referring to in my original post. I am still trying to sort out one thing. Once direst T3 is added to therapy, does your body stop producing T3 on its own? Maybe you answered this in your post and I am missing it (the brain fog is real), sorry.
Can one consider T4 only if the NDT ratio does not work for them? Or as greygoose mentioned, is it too hard on the body (makes sense that it might be). I will also speak with my ND about reducing the NDT and adding T4.🙂
The pituitary is especially sensitive to T3, and often after adding exogenous hormone (replacement meds) the HPT axis signalling translate ‘enough thyroid hormone’ and slows production. Hence the low TSH for many of us (thyroid stimulating hormone).
Obviously if you have reduced gland tissue due to Hashi damage, that will also influence how much hormone you are able to produce yourself.
Many do well on Levothyroxine alone, but many don’t and require just a little added T3 to achieve wellbeing, as conversion mechanisms mean the T3 sum is always more than the amount we medicate.
Your choice of meds will be dictated by your need for T3 as not everybody needs to medicate it. If you do, then NDT is known to provide less of a ‘bump’ than synthetic T3, and to achieve the correct T4:T3 ratio you simply add some Levothyroxine. The down side is NDT is expensive.
If you wish to medicate Levothyroxine and find your FT3 levels slipping, you can add synthetic T3. This regime allows slow introduction to T3 and provides more flexibility with titivation of the T4:T3 ratios.
Thank you for this! I live in the US and am lucky to have my medication compounded. Here, it is not too much more expensive to do this than if I were to get Armor via my insurance. The problem with insurance, as I'm sure you know, is that then I have to see their doctor and fight to get what I actually need instead of what insurance thinks I need.
Just so I am clear... The body still utilizes the T4 even when there is direct T3? So, if I continue on NDT and add some T4, (theoretically) my body takes all the T4 and converts it to whatever additional T3 my body requires?
I really have tried to educate myself. There is so much conflicting information and so many opinions. Even my ND says something completely different that all I have learned here.
Disregarding those on T3 mono- therapy who appear incapable of utilising T4, yes, the rest of us do convert a certain amount (whether medicating or not) but in varying capacities dictated by genetics, age, nutritional status, other health conditions, inflammation/oxidative stress, and much more. Conversion is a key mechanism of thyroid hormone regulation as allows tissues to receive the exact right amount of T3 required at the single-cell level.
In a healthy person T4 ’s synthesis is limited to the thyroid gland where as most T3 is gained from peripheral conversion of T4 in certain areas dependant upon which conversion enzyme. When we medicate thyroid hormones we lose that natural regulation and we might even discourage future production of thyroid glands T4 through pituitary sensitivity but we don’t shut down conversion. What can happen is excess thyroid medication will encourage inactive metabolites as opposed to active T3.
Ideally to prevent risk of excess inactive metabolites we want to take the least amount of meds that bring wellbeing and allow full potential of conversion which also has positive consequence on other hormones. Many find as they acquire wellbeing, their T3 med dose requires reduction anyway as those inhibiting factors mentioned above starting reversing and conversion improves.
The reason there is conflicting advice is because everyone works differently and will respond differently to different meds and different T4:T3 ratios. There is no one-size-fits-all.
I also feel some warmth and stirring around 2 hours after taking my NDT in the middle of the night - but find I can fall back to sleep for a couple more hours - waking up around 6 am.
I only take 1 dose and do dip a little in the afternoon - but at 77 - think that's allowed ??
On NDT you track on the T3 around 12 hours after ingesting the medication -
your levels ' look ' very low - do you run a fasting blood draw and how long do you leave between last dose and blood draw ?
my Free T3 is generally 90/110 % through its range with my T4 at around 25/30% through its range - I have no spiking and if anything run myself slightly ' hypo ' - if there is such a thing.
I'm with Graves post RAI thyroid ablation 2005 and only seem to need 1+ 1/2 grains NDT - maybe because I do not have a fully functioning thyroid ?
I also take an adrenal glandular and need to supplement to maintain my ferritin, folate, B12 and vitamin D at optimal levels - in order to optimise T4 to T3 conversion.
Many people need to take any preparation containing T3 twice a day - though NDT is said to be more slowly released as the hormones are attached to haemoglobin and are more slowly broken down in the gut.
Did you start on T4 only - and know you have a conversion issue and why you switched to a combination treatment option ?
I think once the body is used to having T3 directly - it doesn't do ' as well ' switching back to T4 monotherapy.
Hi pennyannie, I dip a lot in the afternoon and I'm 51, so it seems being 77 and dipping just a little is certainly fine.🥰
I take my thyroid at 5AM ( a few hours later if I have bloodwork scheduled the next day. My blood draw is fasting, but that means there is about 24 hours between the blood draw and last dose. Track on the T3? Could you please explain further?
My test results were actually much better before beginning thyroid replacement. My FT3 hovers at 2.9 now, but it was 3.3 before starting thyroid. My FT4 is 0.7-0.9 now and it was 1.1 before. I had really poor gut health and dietary habits back then, but I do not believe I had a conversion issue. I only started NDT because that is what i was offered. I was never given T4 only as an option. My late afternoon cortisol was also better before beginning thyroid replacement. So I just wonder if my current dose is doing more harm than good.🙃
I see you have Hashimoto's - this is an Auto Immune disease and you will be liable to erratic own thyroid hormone production as your immune system systematically attacks and disables your thyroid.
This can cause ' swings ' in symptoms which ultimately leave you needing more thyroid hormone replacement support as the gland becomes further disabled.
Your thyroid on a daily basis supports you with trace elements on T1. T2 and calcitonin + a measure of T3 at round 10 mcg + a measure of T4 at around 100 mcg daily - with T3 said to be around 4 times more powerful than T4.
The original treatment for hypothyroidism and used successfully for over 100 years to treat hypothyroidism is NDT which is derived from pig thyroids, dried and ground down into tablets, referred to as grains, and contains all the same known hormones as that of the human gland.
Big Pharma came along around 70 years ago and launched their synthetic treatment options T3 and T4 on the back of NDT and then went about gaining market share.
In the UK - we have the National Health System - and free prescriptions for cases of hypothyroidism - and routinely prescribed T4 - the cheapest option which works very well for many thousands of people.
T4 is a storage hormone and needs to be converted ( when needed ) in the body into T3 the active hormone that runs the body - and some people find they can't convert T4 into T3 and continue to have symptoms of hypothyroidism.
Should T4 not resolve symptoms we then need to jump through various hoops to get prescribed T3 either as a small dose alongside the T4 to more replicate one's own natural thyroid production, plus there are some people can't tolerate T4 thyroid hormone at all and need to take T3 only.
Should you wish to try NDT in the UK - you will not get this prescribed on the NHS any longer - due to cost -
I self medicate as do many - I don't have a thyroid ( Graves Disease and post RAI thyroid ablation 2005 ) and seem to need full spectrum thyroid hormone replacement options.
Obviously in the UK if you can afford to go privately you have a choice.
So with NDT you dose to the relief of symptoms and not a blood test - and the blood tests and guidelines were all introduced to be used alongside Big Pharma's treatment options.
So - when optimally medicated on NDT - your blood tests will show a low suppressed TSH with a T3 significantly higher in range - with a T4 possibly much lower in range - than when taking T4 only medication -
so the opposite to how T4 blood tests ' look ' - as then you likely need a high in range T4 to convert to a high enough T3 - to relieve symptoms :
and most doctors interpret / read blood test as per the guidelines which were not written for NDT - and if they are not familiar with how NDT ' looks in a blood test' - why I said you ' track on the T3 ' as this is the active hormone and the most important of all 3 blood test readings.
Thank you! I am in the US. I have my thyroid compounded out of pocket, but it is not too much more than if I used insurance for Armour or Synthroid. I prefer the compounded because there isn't a bunch of extra "stuff" in it.
Even my ND doesn't always seem to understand how to read bloodwork when on NDT. It's frustrating. I really have tried to educate myself (I have read and read and read), but there is so much conflicting information and so many opinions.🙂
My cortisol is high in the early morning, good in mid morning, low in the afternoon, and good at bedtime.
Did you know that cortisol has a circadian rhythm? Having cortisol high in range first thing in the morning is usually a good thing. As the day goes on it reduces and reduces until it is at its lowest, then it starts to rise fairly sharply at about 3am - 4am.
Optimal cortisol levels can be seen in "Example 1" on this link :
Hi! Yes, I have done quite a bit of reading about adrenals. I was referring to my morning cortisol being at the very tip top of the range in the morning (which is fine until I add my dose of thyroid and then I think it makes my adrenals unhappy).🙃 My late afternoon cortisol is quite a bit lower than it should be for the timing. Again, I wonder if this has to do with the large dose of T3 in the very early morning (5AM) and then I am "out of gas" in the late afternoon (around 3PM) because I have burnt through the T3? Just trying to puzzle it all out and appreciate that there are so many knowledgeable souls here .🙂
I had very high cortisol in the early days of treating my thyroid. A 4-part saliva test showed that 3 out of 4 samples had a cortisol level over the range and the other sample (the 2nd one) was over 90% through the range.
I really, really struggled to take thyroid hormones of any kind first thing in the morning. So when I got my cortisol results I started taking my first dose of thyroid hormone (which was T3) at the same time as the best saliva cortisol result (the 2nd one). I know you said you didn't want to split your dose, but that was the only way I could tolerate any thyroid hormones.
Eventually I tolerated what I was taking well enough that I decided to start amalgamating my doses and moving my dose times earlier in the day.
I started taking thyroid hormones in 2013. Nowadays I actually take T4 and T3 both together, first thing in the morning, without any side effects. But I had to work my way to that gradually.
I appreciate this. So you no longer split the dose? Do you mind sharing the amounts of T4 and T3 that you take? (Is that kind of question allowed here?) I know it is a little different for everyone, I'm just curious. My ND told me that my dose, 175mg (not quite three grains), is a large dose!? I do not believe this to be true and I think I need to find a new doctor.
I don't split dose, and haven't done for several years. I take 50mcg T4, 2 days a week, and 100mcg 5 days a week - an average of 85.7 mcg per day. And I take 18.75mcg T3 every day i.e. three quarters of a 25 mcg tablet.
In years gone by, when NDT was routinely prescribed by doctors, patients would most commonly take doses between 2 and 5 grains per day (or so I've read). But you must be wary of such statistics because the T4 and T3 levels in NDT have fluctuated over the decades. The irony is that doctors eventually started claiming that NDT was unreliable in its T4/T3 contents and it should be banned, while at the same time Levothyroxine was being recalled over and over again for poor quality control.
Patients used to be prescribed very high doses of thyroid hormones compared to now. But it was when testing for TSH, T4 and T3 was introduced that doses started dropping and dropping and dropping because doctors think that patients with thyroid disease must have a TSH the same level as that of a healthy person with a healthy thyroid. But a healthy person has a thyroid which produces T4 and T3 in tiny spurts throughout the day and night. Patients with unhealthy thyroids usually take their Levo/T3/NDT in big "lumps" rather than tiny spurts and this affects the production of TSH.
I wouldn't say that 175mcg NDT or Levo is a high dose. But then I'm just a patient, not a doctor so my opinion carries no weight with doctors!
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