One extreme to another - high dose T3

Why do so many people here when they try T3 start on such high doses then wonder why it doesn't make them feel better? Surely the best starting point is to copy nature with a dose of 5-10ug T3 with enough T4 to maintain the TSH around 0.5-2. And if that doesn't work THEN try other combinations. If people start on 20ug T3 or more then this might make them feel just as bad as T4 only and they conclude that T3 does not work for them when it simply may be that they are on too much T3. Why don't people start with the most common sense option first?

My personal experience is that I felt good on 10ug T3 plus 125ug T4 with a TSH of 0.5. But did not feel good on 20ug T3 plus 75ug T4 and a similar TSH. And my blood results reflected that (T3 top of the range and T4 bottom of the range). I also tried out different doses of T4 along with the 20ug T3 ranging from 125ug to 50ug and didn't feel better on any (TSH ranged from 0.05 to 7 depending on the dose of T4). I've currently stopped the T3 completely and am trying out T4 only to see how that compares. Will continue to post updates of my experimenting incase it is useful to others. My current opinion is that I felt worst on 20ug T3, that 10ug T3 was better than no T3 and that keeping the TSH between 0.5 and 2 is the most important thing to feel best.

17 Replies

  • Hello Natalie

    I suppose the answer is that everyone starts in a different place when they try out T3.

    I was on 75mcg of T4 for 11 years and felt well until a big downturn about 3 years ago when my TSH shot up and T4 was increased to 125mcg which gave me suppressed TSH so reduced it to 112.5 but still never felt better. Just started about 3 weeks ago on T4/T3 combo.

    T3 was prescribed by an endo and his advice was 100mcg of T4 and 20mcg of T3. First day I had absolutely horrendous headache, so left T3 out next day and tried 75mcg of T4 and same T3. Since then T4 reduced to 50mcg with increase of T3 to 25mcg. Only been on this a few days but I haven't sprung back into life yet!.

    If this doesn't work might try reducing the T3 to 10mcg and increasing the T4, as it worked for you it might just work for me, thanks.

    Of course I am aware of all the other issues which may prevent my thyroid meds working so going through these one by one and testing adrenals, D3, B12 etc.

  • Thanks for telling us what you tried. I've been trying T3 only going directly from Armour and using the equivalent dose of the T3, which is about 25 mcg., and taking NO T4. It hasn't been long enough to tell if there will be any real improvement.

    I don't know how long you stay on each trial but I hope you eventually find that one that works for you.

  • I have been on 40 mcgs of t3 (split into 2 doses) plus 75mcg of t4 - for about 4 months now and have not felt as well as this for a long time. Weight back to normal through exercise and dieting. ( hadn't worked before ) have still got pains in calf muscles though. Should I try upping my D 3?

  • Redjane, I'm not sure who you are asking but if you have checked your D3 and it is low and even if you haven't tested, I'll presume you are low, I would definitely supplement. Many doctors have prescribed but it is very reasonable to buy on your own. Avoid the one with soy oil if you are getting gel tablets. I use a spray under the tongue now that also contains K2 because I can't seem to raise my level to within range and I tan easily and get plenty of sun. Lately I have read it is better to take a triple dose every few days rather than a daily dose. Personally I have tried 5,000 and 10,000 units and made NO progress. I finally took a 15,000 i.u. twice a week for three months and I am still not there.

  • Thanks for taking the time to help. Will try the 2-3 times a week for D3

  • I found that high T3 (with a low TSH) caused me to get muscle pain. I would feel as though I had done a gym session when all I had done was maybe crouch down the day before! I don't get this when my T3 is 10ug.

  • Actually my endo is keen for me to reduce my t3 dose but he hadn't used blood test results to evidence this it was just his gut feeling that 40 mcgs per day was too much. In view of my muscle pains - perhaps he was right. Will try and see. Thanks for your time.

  • TSH isn't a good indicator of symptoms in a patient. There's never been any research to show that it is (as far as I'm aware) but doctors sometimes assume that it TSH is the "gold standard" of thyroid blood tests. I had many symptoms when my TSH was "normal" but am much better now on T3 only and my TSH is suppressed. It's all down to the individual.

    It's great you've found that TSH works well for you. A healthy person with no thyroid problems will have a TSH of around 1, that's the kind of value you're looking at as well. However I'd always advise someone to look at the actual thyroid hormone test results T4 and T3, rather than TSH which is the pituitary gland.

    It used to be thought that the equivalent amount of T3 to T4 was 1 to 5. But more recent studies have suggested it's more like 1 to 4 or 1 to 3. The endocrinologists I've seen have used 1 to 3. Using this 5mcg is only 15mcg T4 and 20mcg is 60mcg T4. A normal starting dose of T4 is 50mcg so I don't think 20mcg T3 is a high starting dose. Also in the UK there is only one size of T3 pill manufactured and available, the 20mcg pill. So that's two good reasons why patients are started off with 20mcg.

    I was interested in the gene research that's been posted recently. It said there is a certain gene that people have. Everyone has two of them. One inherited from your mum, one from your dad. If neither of the genes are damaged those people didn't benefit from the addition of T3 to their T4 treatment. If one gene was damaged then those patients did feel better with T3 added and if both genes were damaged those patients felt even better from the addition of T3.

    So many you have two good genes and mine are damaged??

    My experience of starting T3 in combination to T4 is an interesting one. My T4 was reduced and T3 added. I felt great for a week or two. Much improved. Then I crashed and felt awful, hideous, I could barely function. If I'd gone back to the endo who prescribed the T3 and had already said he didn't believe in it, I would have been put back on T4 (which had relieved some symptoms but I was still far from well). But I trusted my instincts and felt that T3 had improved me a lot initially. I then saw Dr Skinner and he increased my T3 & T4 (one after the other, not at the same time) and I felt better. Over time I reduced my T4 and increased my T3, feeling improved each time.

    What I think happened at the initial dose is that the T3 was being used in my brain. The T4 was being used mainly by the rest of my body. After 2 weeks the T4 reduction had kicked in. So my body was getting less T4 and this wasn't being replaced by the T3 because the T3 was all being used by my brain.

    But how many patients have felt worse on taking T3 and then went right back to T4 but would have benefited from it if they'd been able to try out different doses? I guess I'm saying the same thing as you but coming at it from a different angle. I needed more and so felt bad on T3 initially, but you find that people may have too much and feel bad.

    What would be good is an information leaflet with a section on how to make the cross over from T4 only to T4 and T3. If you just start taking the T3 on day one you've going to be at a higher dose than 3 - 8 weeks later when the reduction of T4 has completed in your body. When I've had a reduction in T4 and an increase in T3 I worked out myself that it's best to reduce my T4 and wait a week before taking half the T3 increase. Then wait another week and take the full T3 increase. That makes a much more even transition for my body.

    All the best,

    Totoro x

  • I agree with all that Totoro said above :)

  • Me too :)

  • This is very interesting and the 1-3 t3/t4 calculation explains why my doctor didn't want me to reduce my t4 before adding in t3.

  • 'each to their own' I feel the best when I don't have any blood tests done and I don't know what my blood is doing and when I take no less than 150mcg of T3 in a day. I am now taking 180mcg and I still need more, I still have not found my 'optimal dose', though I am a million times better than I was on Levo or Armour or a lower dose of T3.....

  • Dear Sandy12, that is how I take my T3, all at once in the morning as soon as I wake, up, crush it with my teeth and swallow. That is what works best, multi dosing is not as good and just a 'pain' to remember to dose each time, I gave up on that a long time ago :) it's my heart rate/blood pressure/temperature/constipation/dry skin/weight gain which tell me if I am overdoing it (I don't rely on weight too much, I don't think this is incredibly accurate and takes too long to give you feedback, but just monitor). Oh and of course, my heart is not racing and don't have the shakes etc :)

  • My private Doctor, Dr 'M' has investigated it, she cannot think of any reason why I need such high dosages apart from being 'thyroid hormone resistant at cellular level'. If she's 'satisfied' that's what I have I am happy to accept her diagnosis. I don't have a problem with cortisol or vitamins/minerals or iron, she tested me for heavy metal toxicity as well, we can find no be honest I don't 'need' a reason I just know that high doses of T3 make me feel a world better and I accept it, I take as much as I need to feel well :)

  • You're right that people shouldn't dismiss T3 just because they don't feel well straight away on 20mcg. A smaller dose, like you suggest, may be the way to go and slowly increasing until optimal health is reached. Equally some people might actually need higher doses than 20mcg and that may be why they are not feeling any better.

    20mcg isn't really a high dose at all. It is generally a starting dose, in split doses. Of course, if you were previously on T4, going straight to this kind of dose might be too much because of all the T4 still in the system. There are also other reasons, like low iron, that need to be addressed before they can feel well on T3. If you are starting from scratch, 20mcg should be fine for most people (although certainly not all). I was fine starting on 20mcg straight off when I was originally diagnoses, and was able to increase quite quickly, although I know that isn't the case for everyone and, for those people, your approach might work.

    On TSH: This is not an accurate way to measure the status of hypothyroid patients. There has been recent research that shows this. It is fine for euthyroid patients, and hyperthyroid patients to a point, but not hypothyroid patients. The range 0.5-1.5 is what is recommended as a good level for euthyroid patients. Hypothyroid patients often need TSH levels below range. Even Dr Toft, former chair of the BTA who are responsible for the current thyroid treatment guidelines, says that many people will need a TSH below range or even suppressed. Having said that, there are hypothyroid patients for whom these levels work well and, in these cases, the TSH test is quite useful.

    TSH is representative of thyroid hormone levels in the pituitary gland only. It tells us nothing of what is happening in cells in the rest of the body. Different processes are involved in the pituitary and peripheral tissues. One can be very hypothyroid but if conditions in the pituitary are ok, TSH says nothing is wrong when there clearly is. There is an enzyme responsible for conversion of T4 to T3 in peripheral tissues and it is different from the one that does the same job in the pituitary gland so why is the medical profession so hung up on measuring what is happening in such a tiny part of the body to determine what is happening in the rest of it? Some people have the defective gene that Totoro mentioned which means that conversion in peripheral tissues is not working even though the TSH is showing that all is well because the other enzyme is present and doing it's job in the pituitary gland itself.

    My TSH is always below range even when my T4 and T3 are at the bottom of the range. Reducing my dose reduced my T4 and T3 levels but my TSH still did not rise into the range you mention as being optimal. I was hypothyroid and very unwell yet my TSH said I was over-replaced.

    Relying on TSH is dangerous. There are so many reasons why TSH can be unrepresentative of actual thyroid hormone levels including B12 deficiency, adrenal insufficiency, pituitary problems and other problems in the hypothalamus/pituitary/thryoid axis. I am lucky that my T4 gets tested otherwise I would be a mess now with very, very low levels of thyroid hormones.

    I'm pleased you have found what is working for you. It's great that you have found the way to find your optimum dose and that you are feeling better and thanks for sharing. Your approach may well help some people but bear in mind many doctors and patients have different approaches and what worked for you may well not work for others.

    I wish you continued good health :)

    Carolyn x

  • 20mcg is a very usual dose and according to my doctor many people don't feel the effects on a lower dose. I'm on 20mcg now, having built up the dose - as you advise - from 5mcg and aside from an initial improvement I don't feel any better. Everyone is different. Everyone's blood test results are different.

    Although I'm pleased that you're feeling well, when you say "Why don't people start with the most common sense option first?" it sort of implies that people are foolish for following a path other than your own. Some people here are following their doctor's advice and some are self-treating but I don't see anything here that suggests that they're lacking in sense.

  • T3 should be started very slowly. A tiny amount and increase every few days.

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