Interested to know how other peoples test results fair following a reduction in levothyroxine. I am a poor converter and have below range TSH at 0.01 and above range FT4 at 24.6, my FT3 is not great at 4.3, haven't put ranges as I don't have them to hand. I was taking 250mcg but have now had that reduced by GP to 225mcg. I was not asked if I had symptoms of over or under medication as it was a receptionist who rang me to tell me this is what she had been told to do. Incidentally the Ft3 result was from a private test, the nhs only tested tsh and ft4 which I think is pretty standard. The tests were done 24 hours after last dose if levothyroxine. What I'm really worried about apart from symptoms of low thyroid getting worse is putting weight on as I've managed to lose 2 stone recently by modifying diet to reduce sugar and I really don't want to be putting weight back in as I still have a lot of weight to lose..just Interested in hearing other people's experiences. Apologies for long winded post . Still working on improving iron as TSAT was 20% on last private test but usually have low in range ferritin. I have improved B12 but can improve further. Vit D was low in range and I've been working on that as well. I'd really like a bit if liothyronine but think there's no chance if that unless my next private blood test shows it out of range maybe?!
Does a reduction in Levothyroxine usually resul... - Thyroid UK
Does a reduction in Levothyroxine usually result in a reduction in FT3?
fT3 might fall on lower dose levo , but not necessarily ,
it's also possible for fT3 to go up a little because when body senses fT4 level is high , conversion of T4 to T3 is slightly down regulated (by the deiodianes converting more of the T4 to reverseT3 and less of it to T3)
so it' equally possible your fT3 level may stay the same , or even increase a little.
Thank you for replying. Guess time will tell when I get next private nloods done. Should I be testing anything other than TSH, FY4 and FT3 like RT3 if they even test this?
no need to bother with reverse T3 .. . NHS won't , and it costs a fortune to test privately ( has to be sent to USA i think ), and frankly , there is not much point anyway ~ basically if fT4 is high end, then Reverse T3 is very likely to be high for that reason.
Just see what happens to TSH / fT4 / fT3 ( and how you feel) on lower dose.
(give it a good 6 wks before deciding how it feels .. i have made the mistake of spitting my dummy out too soon in the past. because the first 4/5 wks on lower dose i would have sworn i was undermedicated , but then things slowly improved , and in the end i had to admit i felt slightly better on the lower dose than i had on higher one)
Then if necessary, use those new results/ symptoms to push them to try you on a bit of added T3 instead of having to have your fT4 over range .
Great advice. Thank you for taking the time to reply and share your experience 😊
My endo waxed about this idea; dropping Levo to increase T3 production. It worked for approx two days. I then became very ill and it’s taken me months to get back some stability. I just have to accept I can’t convert well. By the time I did test, my already poor T3 level was rock bottom. I don’t think this is a valuable move. However you just never know.
Oh that's terrible. Hope you can improve your FT3. Guess time will tell 😊
Hello Ic1973
I would think your T4 is up too high, if not over the range and this is not a good idea long term.
The accepted conversion ratio is said to be 1 / 3.50 - 4.50 T3/T4 with most people feeling at their best when they come in this ratio at or under -
So if I divide your T4 result 24.60 by your T3 result 4.30 - I'm getting 5.72 - so yes you are wide of the centre and struggling to convert the Levothyroxine.
However we do need the T3 and T4 drawn from the same blood test - which this is not.
No thyroid hormones work well until the core strength vitamins and minerals are up and maintained at optimal - I now aim to maintain ferritin at around 100 - folate at 20 - active B12 125 ( serum B12 500++ ) and vitamin D at around 125.
As for T3 on the NHS - you can look up your surgery and ICB / CCG area as to how many prescriptions they are writing compared to other surgeries and areas - it is a post code lottery and grossly wrong but that's another issue - and obviously if you can afford to go privately all treatment options are readily available - I gave up trying through the NHS and self source.
So go into openprescribing.net and see if your surgery are supportive - though we are not able to see - if in a group practice - which doctor sanctions the T3 prescriptions - and enter Liothyronine as the drug you are looking for.
Just looked back and see you are with Hashimoto's - have you been checked out for pernicious anemia, celiac, gluten etc - as read you are prone to stomach/ gut and certain foods - many forum members follow the research and suggestions of Dr Izabella Wentz who writes as thyridpharmacist.com
Many thanks for your reply. I have a long way to go to get my vitamins anywhere near the levels you have suggested so will concentrate on that. I've not been tested for PA but am negative for coeliac.
It took me a good 18 months to get my levels up and even now I need to supplement ( at lesser doses ) to maintain these core strength vitamins and minerals -
I'm with Graves and post RAI thyroid ablation 2005 :
I now self medicate having been refused both T3 and Natural Desiccated Thyroid on the NHS back in 2018 and am much improved looking after myself.
I am poor convertor too mines only ever reached 4 in range once a brief one time only on first starting Liothyronine (T3), it moved straight back to 3.7 where it usually sits…
I have increased Levothyroxine by 25mcg for few years now but no change in my FT3 so I seem to be well stuck with below 4 FT3 range … I suspect if like me you will have no change, or barely but we are all different and have different reasons for poor conversion.
Many thanks for replying. Good luck in finding answers too 😊
You are on quite a high dose of levothyroxine, but it appears that you need this to get to a T3 of 4.3. You are probably a poor converter (most T3 ranges go to 6.8, so you are not very far through the range). Yes, a very low or suppressed TSH can reduce the conversion of T4 to T3 slightly, but it is not entirely clear by how much this will be influenced, as other things like good nutrient levels are also very important.
At the doses you are taking, it is not very likely that your TSH will come up that much to contribute to the conversion, so reducing your levothyroxine might reduce your T4 to within the range perhaps, but it will quite likely reduce your T3 as well. As you seem to be a poor converter, have you considered taking T3? This way you could reduce your T4 levels to get within the range, and could boost your T3 ?
I can only speak from my own experience with regards to reducing levo due to being on top or slightly over the range and having a suppressed TSH. My T3 level is 5.3 and T4 is top of the range (I am on 100 mcg levo only). A while back, I reduced my levo by 12.5 mcg only (75mcg every other day) and it did not sit well. TSH was still suppressed, T4 was at 17 (which was okay) but T3 fell to 4.7, which was not okay for me and I went back to 100mcg. I recently tried to do 75mcg on two days a week to balance out the T4, but even that is not agreeing with me, as I get symptomatic. I do not like to have my TSH suppressed and my T4 on top of the range, but I may have to accept this, as I find that this is the only way I can feel well and have decent T3 levels without having to think about T3 supplementation. 🤷♀️
Many thanks for sharing your experience. Is the T3 you are using prescribed by the NHS or are you privately sourcing?
Hi there, I am not on any T3 at present - I only take 100mcg levothyroxine - this is why I need my T4 quite high, so I can get my T3 a good way through the range. I do not want to go down the T3 medication at present, hence doing all I can to support conversion to T3. Actually, since I have optimised all my nutrients, especially my B-vitamins and the Vitamin D, my conversion has been a lot better.
Sorry I cannot help you with the T3, but since your conversion is quite poor, it might be worth thinking about adding T3. There are very knowledgeable people here, who will be able to help you. If you are lucky and can get an endocrinologist to prescribe T3 for you, just be very careful at the beginning. We have recently seen cases that they tend to reduce the levothyroxine by a huge amount and start quite high on the T3 - which is setting people up to fail (so they can say told you T3 does not work!). So if you get a prescription, I would ask this forum for some input as well, and usually soft and slowly is the better approach.
Hope you will find a solution that will work for you.
Many thanks. I will try and Improve vitamins first, then get a private blood test and see where that takes me. Shocking re setting people up to fail. Rotten.
Bear in mind free T3 varies through the day -- it's said to be highest between 08:00 and 10:00 (in the euthyroid, I suppose). The level should change according to ambient temperature, although that response is likely to be blunted for us lot.
How long does it take for T3 to come out of a persons system?
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Still feeling cold on Levothyroxine. Low Ft3, add T3?
FT3 Does Matter!
