Would adding T3 to T4 help me with exercise tolerance - anyone have any experience of this?

Hi all. The girls are staying at Grandma's this week and so with a little time on my hands I decided to go for a run. Nothing too big, just a couple of times around the park - around 4km. Nice and gently, took me nearly 25 minutes. This is the kind of thing I used to do every day (and lots more too...) some years ago, even before being treated (I take 150 mcg levothyroxine and tons of vitamins - separately just like you should). I felt great immediately afterwards. However, within about 30 minutes I had to lie down and needed sugar/food desperately - so I had lots of fish and salad, and a home made banana muffin made with coconut oil. I then got a migraine and went to bed early. I got up this morning after nearly 10 hours in bed feeling groggy, disorientated, starving, and generally like I'd been hit by a bus. Now at work and feeling a bit shaky but a lot better - normally a migraine stay with me for 3 days, so this was definitely related to the exercise.

I've been plodding along with T4 and thinking I'm doing OK, and am now thinking it may be time to take matters into my own hands and obtain some T3 to supplement it as I know my (private) endo will not prescribe it for me. Has anyone had experience of exercise tolerance improving after taking a combination of T4/T3? This would help me to work out if I should try it.

18 Replies

  • I keep saying it but it was a light bulb moment for me when I started taking T3 as well as. T4 . I have so much more energy and do lots of excercise and depression And fatigue have gone . Am terrified that my GP will stop the T3 as I know it is a bit controversial - he listens to my symptoms rather than my TSH test results for which I am sooooooh grateful . Hope you find the same. X

  • Thank you! This is just what I wanted to hear. I am a really active person, and the thought that a little run like this can knock me back so much is quite frightening. How did you persuade your GP? My endocrinologist has refused me, saying he has to fight the PCT for every prescription he writes, so he can only prescribe to 'those who really need it' (ie I'm not ill enough!!).

    I notice there is a private GP in my city who will probably do me a private prescription, but that's going to start me down a road of high costs... difficult to put a price on health though isn't it.

  • My GP is pretty well informed and I did originally go to him armed with lots of printouts and info from this website . He agreed to a trial and hopefully saw the improvement in me( lost weight, not depressed etc etc.) have got to go to see endo next week and am very worried that he will put a spanner in the works. Please God as I really am so much better.

  • Good luck with that. Perhaps if you could get backing from your lovely GP to confirm how much you have improved, that would surely help?

  • It's transformed my life. It's been 6 weeks now and I am running everywhere no longer breathless. I hardly use my inhaler I feel alive.

    Mr Dr won't even discuss it with me although my endo encouraged me to keep buying it. If you lose the prescription just buy it privately.

    Give it a try staring a low dose and build up. For 30 years I have felt dreadful on T4 only now I feel fantastic. I grieve the lost years 😔

  • Adding T3 to T4 helped me enormously. I cannot answer your question but as regards exercise, 25 minutes is quite a long time if our bodies have been under attack for a while. It shows that you overdid things by your reaction afterwards.

    I would begin extremely gradually and extend the time slowly next time you feel you have some energy.

    This is a link with general information on T4.


  • Hi. I always have energy now - I am not an ill person. I have a totally 'normal' life and am nowhere near as bad as lots of people on this forum, for which I feel very lucky. I still have some symptoms but I thought I was generally doing OK on just T4, and then had this reaction last night. For me, this amount of exercise is not a lot - I've just not had the time recently, what with working and looking after the kids etc. Before I started taking the thyroxine (and before the kids of course) I would do far, far more.

    Anyway, it has sort of pushed me more into thinking that I do need some T3 too if I want to maintain any kind of proper exercise in my lifestyle (and I certainly do), and I know I won't get it from my endocrinologist or my GP, so I'll have to do it myself.

  • Until things start to change drastically- [& I hope they will] we are all in a private or postcode lottery, or both perhaps.

    Money can short cut through the murk on T3 and good to know it's there -but finding the right NHS support is tricky.

    We are advised to maintain our relationships with GPs etc and appreciate how marvellous they are -but as funding taxpayers we are all too often treated poorly or ignored by them.

    I have a 'listed by here' Endo lined up for later- but don't expoect a good ride getting there, tbh.

    Unless 'ill', [bleeding or begging for help] we are packed off briskly with standard treatment at best.Discussion is very hard to maintain.

    It can't go on like this.Lives are being pushed onto the back burner.

    How long before the Scots Petition filters through the mire of Thyroid management in the UK as a whole?

  • I remembered an article I read re T3 and exercise. I couldn't find it but these are similar:-



  • I think the wisdom that Shaws has demonstrated in her reply to you is meaningful. You REALLY do have to listen to your body when you have an UAT. T4 is a storage hormone so I would suggest you have your FT3 tested as well next time. Both the FT4 and FT3 should be near the top of the range...it could be that you are not converting the T4 tablet into the active thyroid hormone T3.

    Adding T3 to your mix is not an easy ride - so do not look for a quick fix. I too lead an active life - but at 67 I have learnt that listening to your body is the most important thing. I swim loads daily, play tennis, practice yoga and walk my dog as well as running a holiday Guest House and Studio in Crete. However there are days when I really do have to take things more steadily and my energy levels are low - probably during a waning moon :-) :-)

    Maybe share your last blood test with us and maybe we can be more helpful. Have you read up on CoQ10 ? Wishing you lots of energy soon.........

  • Have you had your Free T 3 tested? I managed to persuade my GP to test mine and came back below the ref range. It was then easy to ask for referral to a private endo, who gave me T3 with a private prescription. I then asked my practice if they would pay and they do. I am now on T3 only, using up lots of pots of it and waiting for the day when they say,"no more". Until then... You may find the same and that your practice will pay, once you get an endo to prescribe. Worth a try!

  • Hi. Yes, my endo is very good in that he always tests TSH, FT4 and FT3, but my TSH is always low to suppressed, my T4 top of range and my T3 bottom of range. Its pretty obvious to me what's going on (ie I'm not converting well), and I think obvious to him, but he feels that his hands are tied. He's not being sympathetic though as I think he knows I'd push him if he showed me a chink in the armour!! He can be a bit of a shouty old dinosaur, despite me paying to see him! GP is useless, although happy to do whatever tests I ask the nurse to write on the form. If it was up to her, she'd reduce my dose and make me sick again!

    Throughout all my dose increases, I have never once felt overmedicated, despite this great fear from the medics that 'you may make yourself hyper... heart... bones...etc...'!!

  • I would change my endo, unless he will give T 3. Which area are you? I would not recommend my first one, as he was not particularly helpful but at least he gave me T3 and then Armour. After him, I tried Dr S and am still with him. My practice is happy to supply T3 as long as I do not ask them for advice, as my GP admits she knows nothing about my therapy. Why stay with an endo who is not helping you as much as you would like?

  • ...apologies had not read all your posts !!

  • No worries!! The thing is I'm only 44 and am an ex elite athlete, so doing very little is very frustrating. I'm used to going out and exercising all day every day!! I have taken it very easy for 7 years since diagnosis and having children, and I really felt I was doing a 'little run'. Ho hum. I feel absolutely fine now though!!

    Thanks about the advice re: adding T3. The thing is I am well most of the time on T4 and don't want to upset the balance. However, this 'crash' was a bit of a shock and I'd really like to have more exercise in my life. I don't sit around all day though - I work, run around after kids, cycle, swim etc. Maybe I need to moderate my thoughts rather than my medication?!

  • Hi,

    Adrenals. No none has mentioned them but the exercise intolerance is a classic sign. If you have tired adrenals then taking t3 could make you feel worse..... I would be looking at doing an adrenal saliva test, to see what state yours are in. It's about £70 fom Genova Diagnostics.

  • Good point. Never tested them. There is a private GP who is 'on the TUK list' in my city. She asks for this test before she sees anyone. I keep thinking 'If I go downhill, I'll go and see her' but because I'm generally well I don't wish to upset the boat. I think I may make an appointment with her later in the year when I start to get cold again!!

  • Here's the link to Genova tests thyroiduk.org.uk/tuk/testin... :)

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