Adding T3: Do I really need to reduce levo?

My last bloods were fT4 18.7 (10-19.8), fT3 3.8 (3.5-5.5) and TSH 0.07.

I was planning on stepping down some levo (currently on 150mcg, would drop to 125 mcg) and adding some T3 (maybe 6.25mcg per day to start with) but do I really need to? If my free T3 is low, wouldn't adding a little T3 on its own do the trick? After all, the levo won't suddenly start converting more to T3, would it?

Or am I just being spectacularly dense and missing something fundamental?

18 Replies

  • Hose, you are not being dense. I've done the same thing starting this January: adding 6.25 mcg T3 to 125 mcg T4. I was on 100/12.5 but was getting tinnitus from the T3 at that dose.

    What you'll need to check is if adding the T3 suppresses conversion of your T4 dose and if you end up where you started except with a higher T4.

  • I guess I'd find that out pretty quickly, eh? If I start feeling even more blah than currently. Would that be about a week?

  • Just thinking about what you said about checking to see if the added T3 suppresses conversion of the T4 dose: wouldn't this happen even if I did reduce my T4? It sounds a bit like a death spiral where adding T3 can suppress the conversion of T4, so more T3 needs to be added, so more conversion suppression, until one ends up on T3 only!

  • Am guessing you are wanting to add the T3 as you are not feeling well on the levo only? If so then I would not focus on whether it will suppress the conversion of T4 to T3 -but focus on whether adding T3 improve your symptoms and you feel well. it might be that you are not converting T4 to T3 very well on levo on its own. Have you checked all the usual reasons why this might be happening -such as levels of iron, B12, Vit D, folate etc....? if so there is little more you can do to improve conversion -therefore adding T3 in some format is your only other option.

    Adding a little T3 into the mix as it stands is then worth a try. As your Ft4 is at the top of the range but your Ft3 is mid range then this makes sense. T3 is the usable form and T4 is the storage form and it is only converted one way from T4 to T3 and not the other way. Therefore all that can happen is that your Ft4 will rise if you are not converting at all and you will find then you will need to drop the dose of levothyroxine. However you may have an impaired conversion -ie you convert some but not loads so adding t3 in aids the process and you may find that as you improve you are able to convert more.

    Your only other option is to consider moving across to a natural desiccated thyroid tablets -such as Armour, Naturethroid, WP etc... These have all the thyroid hormones in plus Calcitronin which might help. They don't suit everyone and some people just fair better on levo and T3, or T3 on its own. Am afraid it is trial and error to see what suits you personally....For me it was a natural desiccated thyroid.

    Lastly some people are sensitive to the fillers in tablets whether taking levo or the other forms -the fillers either cause symptoms in their own right or for some reason inhibit uptake. I found cellulose was a filler that seem to inhibit uptake even on a natural desiccated thyroid. Once I moved onto a desiccated thyroid that was free of this filler i made good progress and infact had to reduce my dose as my uptake was much greater!!!

    hope this helps...

  • I do a lot of exercise and it was when I started running that the midden really hit the windmill. I am increasingly unwell on T4 only as I suspect that the speedy four-mile lunch hour walks and seven mile runs on the weekend are depleting the stocks of T3 faster than they can be converted / using more than can be converted from current dose of T4.

    But if I get injured or apathetic (always a risk with depression) then if I base my dose of T4 on how much exercise I do I'll end up massively overmedicated until I start exercising again / a dosage reduction kicks in, and the whole rollercoaster will start again. I think I'd like something a bit more responsive to my needs. And given the low value of the last T3 blood test adding some T3 seems like a good idea.

    However, I will be sure to tell my GP what we need to be on the lookout for. If I understand correctly TSH will be even more suppressed, T4 will go down and T3 will go up if both med levels are okay (is this the case both with and without a reduction in T4 meds?) and I feel well. Otherwise T4 will go up if not. Is that about the size of it? It's a bit bloody complicated!

  • You can just reduce levo by 50mcg and add 20mcg of T3. That should keep you on an even keel. If any signs of overstimulation, just reduce slightly. Take note of your temp and pulse.

    Exercise reduces T3 level and if you aren't on an optimum of hormones you will suffer more as you exercise extensively.

  • Why not try reducing your exercise by half. Your adrenal glands determine how much energy you have available and uses reverse T3 to slow you down. I think that is what it looks like when we see you blood tests of FT4 so high and FT3, so low.

    Your dose of 150 is fairly common and many do well on it unless it is turning into reverse T3.

    In the meantime you might try working on your adrenals.

  • Meant to say also that yes, ferritin now risen from 8 to 140, b12 from 400 to 700-odd, folate mid range, supplementing vitamin D 1000 iu daily. Had two sets of bloods done for latter last summer: one showed deficiency and the other a week later showed well into sufficient range. Most odd.

  • Have you tried supplementing with selenium? That is needed for the enzyme which converts T4 to T3.

    (My endo reduced my T4 from 125 to 88 and put me on 10 mcg T3.........disaster! After that I kept it at 88 and increase T3 to 18.85......not good. Then 100 T4 and 12.5 T3.....blood results were excellent. But I wasn't feeling like 'me'.........increased to 112 mcg T4 with 12.5 mcg T3 and went over i.e. heart and anxiety started up. So decided since T3 is easy to move around while T4 takes weeks, I went to 125/6.25. (I've got a lot of blood test results over the past 3 years so I can see what effect happens when moving doses and also timing after taking T3). I feel better, recover from injury at a 'normal' speed. But I'm heading out to pick up some selenium supps today. I have not tried this yet but given my diet, I find it hard to believe I need it.

    This is why you need to get tested but give it 3 months if you are adding the T3 just to see if T4 does predictable things or unpredictable things. Waveylines is correct: improved metabolism due to increase in T3 dosage MAY improve conversion. Your fT4 may stay the same, or it may go up. My conversion ratio does not change regardless of T3 dose. fT4 moves up or down lockstep with dose. fT3 changes depend entirely on T3 dose. What is unpredictable and can take time is how we feel subjectively in ourselves.

    I'm also experimenting with green smoothies that contain salt (adrenals) to see if the problem with feeling blah by the end of the working day has to do with needing more electrolytes. Just started this week. Sleep is also crucial. I felt fabulous on Wednesday but woke up during the night and yesterday I was just floating around. Losing a couple of hours of sleep at night is terrible. I have no reserve as far as sleep is concerned. Sleep loss = sleep debt. Blah!

  • My daily salt ingestion would leave many a cardiologist horrified as it is, so don't think I need any more of that! Would be surprised if I didn't get enough selenium in my diet but might try a 50mcg supplement (don't want to overdo things, but will leave that until I've tried adding T3 to the mix). It's all a bit chicken and egg, isn't it?

    I get a rapid heart rate and anxiety when both under and overdosed (and even when completely balanced) so don't really rely on those as indicators. Only totally rested pulse and temperature. And I don't tend to go down much under 36.4 but it's enough to give me horrid chills.

  • It is chicken and the egg indeed. You can go up to 200 mcg selenium per day without problem. A number of years ago while under medicated, I peripatetically took selenium but wasn't paying attention if it made any difference. I'll be watching more closely this time around.

    Temperature for me is not an indicator of anything. Even when undermedicated (112 mcg T4 with low fT4 and fT3) I was running at 37.2 to 37.4C. Post menopause? Also excellent cold tolerance but no heat tolerance. I just must get 8 hours of sleep. 6 hours and I'm good for nothing. I would figure it's metabolism if body temp is high like this all the time, but low fT3 belies that.

  • That is so interesting. My endo has reduced my levo again recently because she says there could be long term problems with doses over 100 and I have just acquired a little cockapoo which needs long walks. This coupled with swimming and yoga and I feel shattered. I did not know about the T3 situation and a lot of exercise!! I have always had so much energy in the 14 years since I had my thyroid gland removed, but my dosage has come down weekly from 1050mcg to 750mcg weekly.

  • Hose, adding a little T3 can stimulate your FT4 to convert better. 6.25mcg T3 is equivalent to 18.75mcg T4 so isn't a massive increase. If you feel overstimulated you can reduce T4 to 125mcg and skip the T3 for a couple of days as the higher dose washes out.

  • Thanks, Clutter. I'll do that and see how it goes. It's very difficult going off piste medically, so to speak, to know which way to start adding a new medication. Just in the interest of devil's advocate, which way would you normally recommend to someone with my results profile and who is very physically active?

  • Hose, you are currently optimally medicated with low TSH and FT4 at the top of range but not converting well so I would have advised reducing T4 by 25mcg and adding in 6.25mcg T3 for a week to see how well you tolerate T3 and if no palpitations, anxiety etc. increasing to 12.5mcg if you feel you need more.

  • Would that be with a further reduction of 25mcg Levo, Clutter?

  • hose, no one reduction from 150mcg to 125mcg T4 plus 6.25mcg T3. If you need to increase T3 either to 12.5mcg daily or by taking a little extra T3 when you run there's no need to reduce T4 further.

  • Thanks so much for all your help, Clutter. I'm very grateful to you and everybody else who's helped me.

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