I’ve been taking 100mcg now for around 5/6 weeks but i feel worse now than when I was on 75mcg. I’m due to retest in a few weeks. I’ve been trying to figure out why I feel worse. My lastTSH on 75mcg was 0.3 and my T3 was 52% through the range. So I know I’m not over-medicated and 100mcg has probably pushed my T3 up to 60 ish% I’m expecting. But it may have suppressed my TSH as it was low on 75mcg. This suppression will obviously mean almost zero output from my thyroid which may be why I’m feeling so low in energy. I’m wondering whether this is normal and when I’m on a higher dose (I’m 14st 6lb) the energy will come back. I was wondering if it was better to be on a lower dose and your thyroid still has some output adding to what you’re already taking. On 125-150mcg my TSH will definitely be suppressed. Just hoping I can get back to the gym regularly. Been out for a few runs with the dog this week nearly killed me!! 🤣.
Feel worse on 100mcg Levothyroxine. I felt bett... - Thyroid UK
Feel worse on 100mcg Levothyroxine. I felt better on 75mcg. I’m not over medicated. Is this thyroid gland suppression?
People often feel worse before they feel better. Give everything time to settle including all vitamins at OPTIMAL levels and you will likely improve.
I dont think it was that long ago you were on a low dose of levo and it can take a good 12 montths for all the cells in your body to right themselves. 
Thank you 🙏
I expect your thyroid stopped working a long time ago. Being hypo means that your thyroid needs a lot of stimulation to produce very little hormone. Taking exogenous T4 is quickly start to reduce your TSH to a level that is too low to stimulate the gland. And, that shouldn't really make any difference to you if you're continuing to increase your dose.
Reducing your dose to raise your TSH to a point where the thyroid starts working again is really non-starter because it would make you hypo again, and all the symptoms you've managed to get rid of so far would return.
If you've been taking this dose for nearly six weeks, you're probably ready for your next increase, and that can make you feel bad. You say you think your FT3 is 'probably' about 60% through the range now, because it was 52% through the range on 75 mcg. But, it doesn't work like that. It's not a linear progression. If the FT4 gets too high it can make your conversion worse, and your FT3 can drop, rather than increase. What was your FT4 when you were on 75 mcg?
Thank you FT4 was 60% through range and FT3 was actually 54%
OK, so your conversion isn't too bad. You'll just have to see how you feel after the next increase. It can take a long time to get on the right dose.
"If the FT4 gets too high it can make your conversion worse, and your FT3 can drop, rather than increase."
Greygoose, can you elaborate please? I would like to understand this effect.
When the FT4 gets to a certain point - and that point is different for everyone, but near the top of the range - it starts to convert to more rT3 than T3. This is a safety measure to stop FT3 going too high.
Thank you greygoose. No sarcasm meant, but I thought reverse t3 was something you thought wasn't an issue or was not an issue to test? Am I confusing rt3 with another concept?
No, you're correct. But the point I was making is that if there is more rT3 for the same amount of T4, there is less T3. And it's the lower T3 that causes problems, not the higher rT3. And you don't need to test rT3 to see how well you're converting because you can tell that by comparing the FT4 with the FT3.
I am someone who believes that RT3 IS important to test since, as stated, it can not only reduce the amount of FT3 produced, but it also can reduce the impact of FT3 on the cells, even though it may not actually attach directly to the mitochondria or nucleus within the cells. I think Paul Robinson’s research on the importance and impact of RT3 is worth considering when it comes to the overall effects of RT3. But I am open to more reasoning as to why some feel it is NOT important.
Well, the thing is with rT3 is that there are many, many causes. And only one of them has anything to do with thyroid. And, testing will tell you if it is high, but not why it is high.
So, the thyroid related reason for high rT3 is high in-range FT4 and low in-range FT3. So, if that is what your results look like, you can be pretty sure that your rT3 is going to be high. You don't need to test.
Also, the only solution to high rT3 is to remove the cause, but it's not always easy to find out the cause. But, if you know you have a fever or some other illness, you know that your rT3 will reduce once you recover. If you're on a very low-calorie diet, it will reduce once you start eating more calories. And if the cause is high FT4 and low FT3, rT3 will reduce when you reduce your levo and add in some T3. Why go to the expense of testing when these things are a given and just a matter of common sense?
Oh, so it’s not that RT3 is unimportant, it’s because you can tell if it is a problem/high based on other tests. That makes sense, but I’m thinking that since the body is so complex, why not know for sure vs assuming? What if your TBG is high and not RT3? Seems like it would be good to know if your RT3 is high no matter what the cause so you can take other action if required?
I hear that the RT3 test is harder to get in the UK than it is in the US, so I can see why the recommendation is to not worry about it as much. I figure since it only costs me $25 with insurance here in the US I’m not as concerned about cost.
why not know for sure vs assuming?
Because it's very expensive and takes a long time, as it has to be sent to the US. That's the only place you can get it tested. If it were as easy to get an rT3 test as it is a TSH, yes, sure, why not. Although it's really not that useful. But, that's not the case.
Oh, so it’s not that RT3 is unimportant
Well, I suppose it's important as an indicator of a problem, but it is NOT the problem itself. Rather like TPO/Tg antibodies.
What if your TBG is high and not RT3?
You tell me: what if? Does that even happen?
Seems like it would be good to know if your RT3 is high no matter what the cause so you can take other action if required?
Why? What other action? The only action is to remove the cause, and if you don't even know what the cause is - because the test won't tell you - how can you take any action? You could consult the list of 'other causes', but most people don't have that list. And thousands of people must have elevated rT3 without even knowing it - and they cerainly won't find out from there doctors because the majority don't even know what rT3 is. So, I come back to the question: why bother? And certainly why make such a song and dance about it like it's the Wicked Witch and the boogeyman all rolled into one? It frightens people and leads them down an interminable rabbit hole with no way out. It's unkind and unhelpful to tell people that their problem is probably rT3 when it's not the rT3 at all. Why not just explain the real problem?
Thank you for explaining this so clearly!
Glad it helps.
I can understand your reasoning for not testing RT3 on a grand scale given it’s cost and limitations, but I personally would want to know if mine was high if I was feeling unwell so at least I could TRY to find the cause, however hard it might be.
Have you had yours tested.
Yes, and it was at the lower end of the range. However, my son’s RT3 was quite high while on T4 only, and he was feeling poorly. His doc changed him to T3 only (after a stint on T4 and T3) and his FT3 went up to the upper qtr of the range and his RT3 dropped below range, and he now says he’s never felt better. (Which is wonderful beyond words since he’s been feeling depressed and miserable nearly his whole life, even when on T4 only treatment.). Not sure just how big a role RT3 played in all this, but knowing it was high enabled his doc to make the required changes to make a big difference in his life. It may have been possible to decipher that his RT3 was high based on other tests, but I felt actually knowing it was high was better.
Sounds a bit belt and braces, to me. If you test FT4 and FT3 I can't see the need for rT3.
But, obviously, if he went onto T3 only, he rT3 would drop, whatever the cause. Because there's no way of making rT3 without T4.
I've never had mine tested but I should imagine it's been pretty high at some points because I was taking so much levo in an attempt to feel better - 200mdg+. But I'll 100% certain it wasn't the rT3 itself that was making me feel ill, it was that I wasn't getting enough T3. I need high doses of T3, 225 mcg at one point!
Still, I think we've squatted ockerdoc 's thread long enough. So, let's leave this discussion there. My apologies, ockerdoc.
You could try splitting your levo dose. For some of us the spike of all the day's hormones entering the system in one go is too much. We find it beneficial to split the levo dose thereby lowering the level of the spike and being gentler on our body. Maybe your body doesn't like 100mcg all at once.
Some folks have found that they seem to absorb the levo better in 2 doses and some find it leads to better conversion. I can't comment on either as I have always taken my levo in 2 or 3 daily doses as it was the only way I could tolerate levo.
might be worth giving it a few more weeks as well? Looking back I always felt worse until I felt better after a dose increase. Took me several attempts to find my correct dose (100 mcg) because I kept dropping back due to feeling worse. If I had given myself a bit more time I think I’d have been steady earlier on in the journey. I would neither decrease or increase at this point. Maybe give it a good 4 more weeks (if you can) and see how you feel then?
Thank you 🙏
2 things spring to mind.
1. Lots of people find exercising too much for their thyroid. Perhaps try something gentler to begin with.
2. Perhaps your body can’t handle the extra 25mcg? It might be better to titrate slowly from 75mcg to 87.5mcg for at least 6-8 weeks. For me, this gentler approaching has been best as I edge closer to 100mcg and potentially higher doses.
As it’s only been a few weeks, it could settle on its own too.
Thank you 🙏
Getting the perfect dose is a roller coaster ride. I felt worse with each dose increase that would eventually straighten up. Up and down. You will get there, but it takes time and often suffering for a week or so with each increase.
Thank you yes hoping my next dose will see another improvement.
Current guidelines recommend a levothyroxine dosage of 1.6 mcg per kg per day based on your body weight. I'm still under medicated based on my weight, but i'm not suffering to bad and my doctor so far refuses to raise my dosage. I should be on 119mcg of Levo. I'm on 100mcg and have been pushing for 112mcg. My TSH is slowly rising back up, but still "in range" blah blah. As long as I completely avoid gluten, dairy, sugar and high FODMAP foods, I'm good. If I slip up, I am in intense bone, muscle and kidney pains for a few days. I highly suspect Celiac/Coliac disease, but refuse to eat gluten to find out. My blood tests have shown a steady inflammation for 2 years.
My worse increase was from 50 to 75 mcg . I felt like a nervous wreck for weeks. I was close to ditching the levothyroxine completely. But like you posted it on here and people told me to stick with it so I did. My increase to 100mcg though was opposite felt fantastic for 10 months until just recently old symptoms are starting to slightly appear. Stick with it I'm sure it will improve. Will be interested to see if you get another increase in time as you are same age and male .
Thanks Keith what is your weight if you don’t mind me asking? If we go by the 1.6mcg/kg I should be on close to 150mcg so maybe 125mcg will give me what you had on 100mcg 🤞
What brand are you having to compound your new dose?Always consider having the same brand.
I had terrible side effects by using 3 different brands to compound my dose some years ago.
It's worth reading the new prescribing advice for patients who experience symptoms on switching between different levothyroxine products. These were the symptoms reported by patients associated with certain brands of levothyroxine or by switching between brands: fatigue, headache, malaise, anxiety, palpitations, pruritus, nausea, myalgia, dizziness, arthralgia, feeling abnormal, alopecia, depression, abnormal weight gain, and insomnia.
Some people don’t do well on TEVA due to a filler called mannitol.
gov.uk/drug-safety-update/l...
Thank you I order my own Synthroid online so I’ll just be cutting tablets etc if I go up to 125mcg.
That’s interesting. Do you live here in the UK or US? I also order my own Synthroid but when I moved to the UK from Brazil, I tried different levothyroxine brands here with no success and decided to go back to Synthroid. I now have reduced mine due to combination therapy with liothyronine which has been amazing. I’ve never felt so good in 30 years of being hypothyroid.
Thanks KC I’m in the UK..did you not convert well? Glad you’ve finally found something that works. I hope I get there.
My TSH, free T4 and free T3 were optimal most of the time on levothyroxine only, but I've always felt symptomatic to some degree until 5 years ago when things got worse after I moved to the UK. I tried most brands available here but was still symptomatic. I was always lethargic and my other symptoms were brain fog, joint pain, dry skin, weight gain, the list is endless. Even when I decided to get back on Synthroid, despite getting rid of some of the symptoms, I was still poorly. I got referred to an endocrinologist by my GP, but it took them 2 years and 3 appointments to give the trial. I can say it's life changing. After only 3 months I feel like a different person.
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