Why even adding T3 is not helping?: Hi all... - Thyroid UK

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Why even adding T3 is not helping?

1366acul profile image
23 Replies

Hi all. Please help I'm really desperate. I've lost my thyroid 5 years ago and been struggling ever since. I was on 200 ug levothyroxine/day for long and experienced tiredness, hair loss, depression, low sex drive, emotional instability and strong social anxiety that destroyed my life. Six months ago I finally maaged to get cytomel (T3) to raise my FT3. I started with 5 ug/day (reduced levo to 150) and now I am taking 40 divided throughout the day and still suffer from the same symptoms!! How can it be? My FT3 is much higher now so I'm absorbing it. Is my body not able to use the synthetic T3? Has anyone experienced that? And maybe had more luck with NDT?

Labs on 250 levo: TSH 0.01 (normal 0.5-4); FT3 3.1 ng/l (normal 1.9-5.1); FT4 2.5 ng/dl (normal 0.9-1.7)

Labs on 175 levo + 40 cytomel: TSH 0.01 (normal 0.5-4); FT3 4.8 ng/l (normal 1.9-5.1); FT4 1.6 ng/dl (normal 0.9-1.7)

Reverse T3 has always been low so this is not the problem..

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1366acul
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23 Replies
Marz profile image
Marz

How are your levels of B12 - Folate - Ferritin - VitD ? All need to be optimal for thyroid hormones to work well in the body.

Baobabs profile image
Baobabs in reply to Marz

I never feel good unless my levels of these vits/mins are constantly optimal, diet good and I take regular exercise, despite good levels of thyroid hormone.

1366acul profile image
1366acul in reply to Marz

Actually they are all good, and I even took the vitD pretty high but did not improve symptoms...

Marz profile image
Marz in reply to 1366acul

Maybe complete your Bio to save members asking irrelevant questions 🤔

Maybe you reduced T4 too much in the beginning ...

1366acul profile image
1366acul in reply to Marz

Thanks, I will. I am a newbie here

Marz profile image
Marz in reply to 1366acul

Yes I know as I checked you out before replying ! You will soon get the hang of it all 🤔

jimh111 profile image
jimh111

Have you been on lower doses of levothyroxine in past? How did you feel then and what were your blood test results? These could be symptoms of too much hormone.

1366acul profile image
1366acul in reply to jimh111

I did, but I felt even worse, that's why I believe I am still hypo and I had so much hope that adding T3 would make me feel good again. Maybe the dose is just not high enough...

jimh111 profile image
jimh111 in reply to 1366acul

Possibly, but do you have some results from when you were on e.g. 100 or 150 mcg levothyroxine? It would show how your deiodinase was working at the time. It's possible you would do better with your levo dose cut substantially and staying on 40 mcg liothyronine.

1366acul profile image
1366acul in reply to jimh111

Here is on 175 levo, the dosage I was started with after the thyroidectomy:

Labs on 175 levo: TSH 0.56 (normal 0.5-4); FT3 2.4 ng/l (normal 1.9-5.1); FT4 1.5 ng/dl (normal 0.9-1.7)

Here I had even more hypo symptoms, and since my TSH needed to be suppressed they upped it to 250. It was better, but still FAR from feeling well.

It looks like T3, at least the synthetic version as I have never tried NDT, does not work for me. I could understand that if my rT3 were high, indicating D3 dominance, but apparently it is low whenever I measured it

jimh111 profile image
jimh111 in reply to 1366acul

OK going from these numbers your fT3 and TSH are rather low given your fT4 is ideal for someone on levothyroxine. There is subnormal TSH secretion and I believe this low TSH leads to reduced deiodinase, specifically type-2 deiodinase (D2). The brain is reliant on D2 for T3, it prefers to take in T4 and use D2 to make T3. Consequently you need for serum T3 to overcome this form of brain hypothyroidism. The T4 in your blood will not be doing much. Also, taking lots of L-T4 doesn't help as this increases D1 and reduces D2 activity.

I would try reducing your levothyroxine substantially, maybe down to around 50 mcg and see how you do, it might resolve your symptoms which seem a mix of hypo and hyper. I suspect your TSH will remain low as there is subnormal secretion. If this doesn't work you could try NDT as some patients report it works when levo / lio doesn't. This may be so, there is no good evidence either way but it nothing else works it seems reasonable to try.

1366acul profile image
1366acul in reply to jimh111

Interesting point. Actually the subnormal secretion makes sense, since even before surgery when my thyroid was basically falling apart my TSH never went above 6. I might give the low dose a try but that scares me a bit, so I think I’ll go for NDT first. Thank you!

jimh111 profile image
jimh111 in reply to 1366acul

I'm in a similar situation and I find 40 mcg liothyronine plus 50 mcg levothyroxine works fine. I'd try this first as you have control of the T3 / T4 ratio. The extra T4 will not be doing anything for you because it will increase type-1 deiodinase which is not what you want (gets very complicated). I don't miss the extra T4, assume it will be the same for you. Try skipping a few days levothyroxine.

1366acul profile image
1366acul in reply to jimh111

Sounds reasonable I will give it a try. Thanks!

1366acul profile image
1366acul in reply to jimh111

Btw I've checked your website, very interesting work indeed! But if D2 has such a crucial role, as you write, how can people do so well on T3-only?

jimh111 profile image
jimh111 in reply to 1366acul

I find I need 40 mcg L-T3, occasionally up to 50 mcg. This gives considerably higher fT3 levels than normal, it's difficult to measure because of the short half-life of T3. I do take some L-T4 about 50 mcg and find a small benefit, I also prefer to have some T4 in my system just in case it is needed for some undiscovered reason.

The brain is the most important organ for D2 apart from perhaps the pituitary. The brain gets 80% of its T3 by converting T4 to T3 by the D2 pathway, it gets the other 20% of T3 from the blood. (I believe these figures come from experiments on rats, you can't euthanase humans and explore their brains). My argument is that if D2 activity is reduced (by subnormal TSH secretion) then organs that rely on D2 will be hypothyroid.

We can bypass this mechanism by increasing blood T3 levels, by taking liothyronine. There will come a point when the brain is able to obtain sufficient T3 from the blood due to higher blood T3 levels. That sorts out the brain reasonably well. There is a real concern about other tissues, particularly the heart (which probably has some D2 activity). Surely high fT3 levels will make tissues that do not rely on D2 thyrotoxic? I think this is so to an extent, I don't like it but I have no choice if I want to function normally. In practice I find everything seems to be OK, my pulse is steady and normal and I'm healthy and feel well. There are other mechnisms that regulate cellular T3, such as serum transport proteins and D3 which converts T3 to T2.

In short L-T3 therapy seems to work OK. I don't like it, I'd rather we fixed the problem and restored normal TSH secretion. I do try and stay on the lowest effective dose of L-T3 to minimise any undicovered risks. The first step is to understand what happens when TSH secretion is lower than it should be, that the effects are much more profound than at first sight. If we can make patients and endocrinologists aware of this then the medics can carry out studies to address the root causes rather than using L-T3 therapy.

People do well on L-T3 therapy because they take supra-physiological doses than override the need for D2 activity. This may not be safe but it is safer than remaining clinically hypothyroid.

1366acul profile image
1366acul in reply to jimh111

I see. Could you tell me how you split your dose?

in reply to jimh111

A TSH of 0.5-1 is usually considered ideal in people on T4 only, along with high-in-range FT4 levels (provided the T4 to T3 conversion works optimally).

I am curious about the statement about low TSH and deiodinisation. Most people on any form of T3 have a low or even suppressed TSH. But that should not be a problem as long as you take T3 and don't depend on conversion...if I understand what you are saying correctly?

1366acul profile image
1366acul in reply to

Actually many people on levo (T4-only) do not feel well unless TSH is lower than that because levo lowers T3/T4 ratio and also inhibits D2. Especially people without a thyroid like me need a suppressed TSH to compensate, that can be obtained by T4, T3 or T4+T3/NDT. If all the "rest of the planets" are aligned, then T4 will be enough. But for many reasons it might not be the case. In my case one of the reasons is the mutations I have in the genes that code for the enzymes that regulate thyroid hormone conversion (I am heterozygous for all the 3 most established polymorphisms of DIO1 and DIO2)

in reply to 1366acul

Interesting! There seem to be so many subtypes of hypothyroidism and this disease is much more complicated than most doctors will realise...

jimh111 profile image
jimh111 in reply to

Many patients on levothyroxine monotherapy do OK with a TSH in the lower part of its interval and fT4 near the upper limit. Theoretically at least they will not be quite as good as the healthy population, this would theoretically be put right if they had a little slow release T3 to make up for the loss of T3 secretion from the thyroid and the loss of thyrodal T4 to T3 conversion. So, these patients are probably not perfect but that doesn't worry me, it's low priority, there are so many patients who are dreadful, let's concentrate on them.

You can overcome conversion problems by taking T3 but it will never be perfect and may give risks. Ideally you would fix the original problem but usually that is not an option. It's best to try and avoid suppressing TSH but it is not always an option. In many cases TSH is not truely 'suppressed', it is very low because the thyrotrope is underperforming.

SlowDragon profile image
SlowDragonAdministrator

Recommended on here that all thyroid blood tests should ideally be done as early as possible in morning and before eating or drinking anything other than water .

Last dose of Levothyroxine 24 hours prior to blood test. (taking delayed dose immediately after blood draw).

This gives highest TSH, lowest FT4 and most consistent results. (Patient to patient tip, best not mentioned to GP or phlebotomist)

If/when also on T3, make sure to take last dose 8-12 hours prior to test, even if this means adjusting time or splitting of dose day before test

Is this how you do your tests?

If you add your most recent vitamin results members can advise on possible next steps

1366acul profile image
1366acul

Yes, always taken my hormones only after the blood withdrawal and last dose of T3 was at 18.30 the day before, I will post my vitamin labs in the bio. I am just getting to know this website. Thank you!

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