Hi, can I borrow your knowledge/experience please?
I started Carbimazole in November after 2 years of hyperthyroidism, I don’t have Graves, nodules or thyroid cancer and all antibodies are negative. The carbimazole reduced my FT3 to 6 from 36, range 4.3 to 6.8. It hasn’t done anything to my FT4 or TSH - both are very low.
My Endo doesn’t know what to do and is trying to refer me to another hospital and has told me to remain on 25mg Carbimazole and take as much Propanolol as I need but not to exceed 360mg- I stopped propanolol in December. I’ve been declined block and replace unless I have RAI.
I think I’m now hypothyroid and want to reduce/stop the Carbimazole.
Feb 2025 test results:
FT3 6 (4.3-6.8)
FT4 <2 (7.7-15.1)
TSH 0.02 (0.34-5.6)
Does this look like hypothyroidism please?
Thanks for reading.
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Mandyj2
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I don't quite understand as Block & Replace is a treatment in its own right focused on saving your thyroid gland and not to have definitive treatment - such as RAI ?
The Propranolol will have also been slowing your conversion of T4 into T3 - and would think if you stopped this in December it should be out of your system by 6 - 8 weeks time -
So if you start now easing off the Carbimazole your T4 will start to increase but you risk your T4 converting to T3 - so please go very slowly - as your T3 is already at 6 and towards the top of the range.
Hello Pennyannie, thank you for helping so quickly!
I’m a bit baffled too. I think I’m not fitting into a box so being pushed into RAI as it gets me off their books faster.
I’m now waiting for a referral to another hospital and don’t know how long that will take so I’m going to start reducing the AT now. I think my GP will do tests, failing that I’ll use Medichecks.
As well as being aware of known physical symptoms to watch out for - you might find it helpful to monitor yourself on blood pressure, pulse and body temperature AM & PM -
I did this when self medicating NDT and rather than just wait on a blood test weeks away my body did give me clues as to what was going on the inside as I increased my dose.
Just take a measure of each first thing in the morning before doing anything else - and late afternoon and ideally they should all stay pretty constant showing no real increase in your internal body engine and metabolism.
Just some sort of insurance - you're not going too fast too soon ?
Thanks Pennyannie, good ideas about tracking BP and temp. I stopped doing BP in December as I felt so well. I’ll get a thermometer in the morning.
I knew the Carbimazole would drop the levels but I didn’t think it would be so fast. I’m very cold, can’t feel my toes and forcing myself to eat, two weeks ago I was eating a meal every two hours and sweating like a pig!
I won’t do anything quickly, i daren’t risk numbers going high again and feel a bit uncomfortable being in between doctors. I had to wait nearly a year for the first Endo apt and hope it’s not as long for Oxford.
I think I felt better around Christmas because the Carbimazole was bringing my FT3 down. On the 12th of December my FT3 was 23.9 and on 21st January at 7.9. Somewhere in between these numbers I felt good. I started to feel cold/slow/heavy around two weeks ago and initially suspected it was a cold.
Ok but you also had Propranolol in your system then and maybe it still has a place in your treatment regime -
Trouble is blood tests tend to run a couple of weeks behind symptoms being tolerated so just thinking - possibly overthinking :
Having read your original post the research papers linked by PNails have opened up a whole other area for me - and even rereading these I feel out of my depth - could this be dove tailing into your menstrual cycle ?
i think until you see the ' specialist ' we are all a bit lost - Helvella has suggested spitting the AT drug if you don't already - maybe this will make symptoms more tolerable ?
I did an Advanced Thyroid check with Medichecks in September 2022. Here are the results;
TSH:3.54 mU/L. (0.27 - 4.2)
FREE T3: 3.93 pmol/L (3.1 - 6.8)
FREE THYROXINE:17.8 (12 - 22)
I had started HRT a year before after getting low estrogen numbers in GP blood tests and couldn’t understand why I felt so hot. I did another thyroid test with Monitor My Health in November 2022, results:
FT4: 8.7 (12-22)
TSH; 0.06 (0.27-4.2)
FT3: 7 (3.1-6.8)
In 2017 I had low TSH numbers but FT4/FT3 not tested. I was told to eat more greens, I didn’t think anymore of this.
Thanks - so years ago you would be diagnosed hypothyroid and treated with thyroid hormone replacement once the TSH was over 3 :
Symptoms start to present when the TSH creeps over 2:
So you were hypothyroid in September 22 but not ' bad enough ' to meet NHS guidelines - did you have any antibody readings there or TPO / TgAB ?
A ' euthyroid ' well thyroid not on any medication and of no cause to be concerned would show a TSH at around 1/.20-50 with a T4 at around 50% and a T3 at around 455 through the ranges -
So your 22 results show your T4 at around 58% with your T3 at around 22% -
so we have an issue there of too low T3 and your thyroid function failing -
What were your inflammation, ferritin, folate, B12 and vitamin D - biomarkers in these Medicheck results September 22 ?
By November 22 - your thyroid looks to have crashed -
TSH under the range - T4 under range with a T3 ' just ' over range -
was this highlighted by MMH and picked up by your doctor and a referral / treatment started and this the beginning of your ' thyroid health issue ?
Thanks Pennyannie, I moved due to the pandemic and didn’t have a local GP when both private tests were done. I joined a surgery after the MMH test in late November 2022 and a full blood count was done. As my TSH came back at 0.27 the FT4/3 weren’t tested - I think this is the lab decision. The symptoms that got me to the GP were that I thought I was having a mental breakdown as couldn’t keep still, tremor, stomach rumbling constantly when eating huge amounts, weight loss and feeling boiling then freezing, nausea, dizziness.
Medichecks results Sept 2022:
VITAMIN B12 - ACTIVE>150pmol/L. (37.5-150)
VITAMIN D- 150 (50-200)
Folate: 16.59 >3.89.
Ferritin: 95.9 (13-150)
TPO: 9 <34
TGAB: 11 <115.
Inflammation: 0.73 (0-5)
If these results show hypothyroidism then this could be what I have and I’ll be grateful to know, I’ve tried to accept that I don’t know as chasing a diagnosis has been tough. The GP and Endo have run antibody tests and all have been negative but I got vitiligo on my throat at the same time as the symptoms started in 2022 and this feels like it’s more than a coincidence!
Vitamins and Minerals all optimal - inflammation low - and negative for TPO / TGAB - so in theory rules out Hashimoto's - though some need a scan/ultra sound as not everybody has o/range Hashimoto's ABs.
Thanks for the links Pennyannie. The Vitiligo Society state hyperthyroidism is a trigger for Vitiligo, I think mine is connected as it’s on my throat, surrounding my thyroid and nowhere else on my body.
All symptoms started in Autumn 2022, I had Covid for 3 weeks in the previous April.
I’ve had two thyroid ultrasounds and both came back normal, is there any other diagnostic test for Hashimoto please?
I've found several research papers detailing increased incidence of Graves etc post Covid vaccine which I think I remember you saying you didn't have -
i think in this case ,the ft4 is unlikely to rise even if carbimazole is lowered , because fT4 level was more or less non existent even before carbimazole was started . (before treatment there was extremely high ft3 , supressed ft4 and supressed TSH ~ T3 toxicosis)
so i think lowering carb would allow fT3 to rise again, but would probably do nothing about the low ft4
i would have thought that bock and replace would be the obvious thing to try ,, but endo refusing to go there
very unusual isn't it, and tricky since they are refusing B&R ....i'd still be tempted to try lowering carbimazole very slightly (but keeping a very close eye on ft3 levels and monitor heart rate / temp daily to be on the safe side ) , just to see if allowing slightly higher ft3 level improves symptoms a little while waiting to see oxford bods.
“I’ve been declined block and replace unless I have RAI”
Ridiculous, if you had RAI you’d have no need to block. I’ve no idea where these doctors justify such statements.
You have undetectable TSH & FT4, but if you stop carbimazole your FT3 is going to go over range.
You’ve no diagnosis of cause just inexplicable high FT3 - block & replacing T4 might lower that.
That’s a moderate carbimazole dose, some start higher, but long term, I would view 25mg a high dose.
Do you take any supplements, herbal / natural remedies.
Many say they feel better a little hyper than hypothyroid. Long term hyper has greater health risks on balance eg with heart & bones. but surely it’s the drs goal to get both your FT4 & FT3 in range.
Thanks PurpleNails. I’m going to email the endocrinology dept now with links to B&R. I’ll speak to the GP too as they’ve been really supportive. I daren’t stop the Carbimazole but am struggling to continue it at this dosage as I feel like I’m turning into a rock.
I’ve been taking D3 with K2 since getting an osteopenia diagnosis last month. My vitD levels have halved in about 6 months, the Endo is looking into why. I started magnesium every night about 4 months ago and try to eat healthily.
I don’t know what Oxford will do yet, I’ve just been told that I’m being referred as Endo dept don’t know what to do next.
British thyroid foundation create patient leaflets for NHS hospitals.
Their leaflet about antithyroid medication describe B&R & there’s nothing about it being reserved for those who have had RAI.
Ask if you can very slightly reduce carbimazole, they will argue against it because TSH low, & FT3 high end of range, but if you empathise symtoms & that FT4 is low & they refuse B&R, why shouldn’t you try to feel better.
if they are refusing to try block and replace......
(which seems the obvious thing to try, i cant fathom why they won't try it when it's patently obvious how low fT4 is )
anyways , if Mandyj2 tried lowering carbimazole very slightly , while keeping a very close eye on ft3 levels to make sure they don't go stoopidly high again, then possibly that might improve how she feels while waiting for oxford endo's to see her.
ok, allowing slightly over range fT3 is not a great plan ,,, but it doesn't seem like NHS has a better one at present .
Thanks tattybogle, I’m putting together an email with this info and sending it to the 3 endocrinologists in the same department. All 3 have talked to my surgery as I can see the notes on my file. Really appreciate your help here, thank you.
Thank you so much PurpleNails. I’m attaching the leaflet to the email. I’ve felt like I’ve had to beg for medication from day one, it took 6 months to get Carbimazole prescribed and only because my GP refused to increase Propanolol. Two weeks after starting Carbimazole the heavy RAI pressure started with the threat to discontinue it.
I’ll arrange TFT’s and reduce to 20mg Carbimazole but I’ll wait until Friday in the hope that the Endo replies soon.
I’ve found a private Endo who I *think* may prescribe B&R quickly, I think I need a back up plan.
I now understand all the other members here who don’t feel heard as how they feel is ignored.
I heard an increase in reports lately that B&R isn’t done in a particular area, isn’t indicated in a particular case or isn’t done at all. I’m starting to believe endocrinologist are not experienced enough to manage it so are making these false excuses.
There is a down side of B&R as it requires higher doses of antithyroid & masking what naturally is happening, those put on B&R have a history of being “neglected’ because stabilisation is more “fixed”, but there’s has to be exceptions where it’s obviously required. This is definitely one of those cases.
The simple question which hasn’t yet been answered is where are your T3 levels being produced from? you had uptake scan, which was “normal” so how is this possible?
RAI would technically be destroying a “normally” functioning thyroid wouldn’t it? but they will go there, but refuse B&R?
Way out of my depth, looking at articles it’s exceedingly rare.
struma ovarii would require surgery initally. “adjuvant (RAI) therapy in malignant struma ovarii remains controversial due to the paucity of information and the lack of large prospective trials”
I’m not sure the predicted outcome if used prior to any surgery, for the reduction of functioning extra thyroidal tissue. It might need greater dose to sufficiently ablate.
no, i don't think i has been , my brain was just 'wandering out loud' like how they work. ( or it was ...it isn't now ~its wondering about eating chocolate biscuits )
It’s not Struma, I’ve had the all clear from a lovely gynaecologist after an MRI. The MRI found a 5cm mass in the liver and I’m waiting for a hepatology appointment in early March. I don’t know if this is connected to thyroid symptoms and am really hoping it’s a common cyst. I can’t feel it and don’t have any liver pain etc.
I’m hoping that a three month wait to see hepatology indicates it’s not serious!
Thanks tattybogle. It’s not Struma Ovarii. Initially they thought it was and sent me for a scan , I wasn’t told and assumed it was a thyroid scan, on arrival it was a vaginal scan. The results showed a large ovary and a gynaecologist told me they suspected Struma and that a thyroidectomy and full hysterectomy would be needed. I was sent for an MRI and weeks later to a different gynaecologist who told me there was nothing wrong with my ovaries and the initial us scan was a common error. That was a happy consult!
phew ... so that still leaves the curious question of where the heck is all that T3 coming from then ??
ps can't quite get my head round why a thyroidectomy would be needed if it was struma ovarii,..... would have thought they just needed to remove the struma thing ,,, but anyway ... way above my pay grade .
Sorry you are such an 'interesting' case. can't be any fun at all.
I’m not sure why a thyroidectomy would be needed either. My GP couldn’t advise and my endo didn’t ever discuss it. I read research papers which suggested that Struma ovarii is usually recognised when patients are in a thyroid storm, in A&E etc. thankfully neither has happened to me! I wondered whether a thyroidectomy was done as an emergency to bring thyroid levels down/ reduce heart risk but I don’t know. I was more terrified at the mention of hysterectomy as until the tumour is removed they can’t actually diagnose Struma, something to do with the amount of thyroid tissue in the tumour.
I’m really, really hoping I have hypothyroidism and I’ve had some sort of hyper flare!
if it was just a hyper phase of hashimoto's then it's still very weird to have virtually no T4
when the excess thyroid hormone is coming from autoimmune damage to thyroid follicles. you'd expect both T4 and T3 to be high , not just T3 . In some cases T3 might be higher than T4 , but to have virtually no T4 like you have is very hard to explain.
"2017 ... I had low TSH numbers but FT4/FT3 not tested
All symptoms started in Autumn 2022, I had Covid for 3 weeks in the previous April"
note ~we know covid can upset previously stable thyroid levels , eg they have found increase in new onset graves cases, or relapse in previously stable graves patients .
"September 2022
TSH:3.54 (0.27 - 4.2) ..bit higher than you'd expect , but could be all sorts of reasons
FT4:17.8 (12 - 22)
FT3: 3.93 (3.1 - 6.8).. towards the low end but not conclusive of anything .
I had started HRT a year before after getting low estrogen numbers in GP blood tests and couldn’t understand why I felt so hot.
November 2022:
TSH; 0.06 (0.27-4.2)
FT4: 8.7 (12-22)
FT3: 7 (3.1-6.8),,, by this point something is causing high T3 levels ,,, high enough to lower your TSH, and as a result of no stimulation from TSH , thyroid is now not being asked to make any more T4 /T3 , hence T4 is now low , due to thyroid being more or less 'switched off' , ( but still doesn't answer the Q of where theT3 is coming from).
"The typical hyperthyroid symptoms started in October 2022, bloods have been done monthly by GP
in my opinion , (which is struggling to make sense of this frankly) as your fT3 has been too high for over 2 years now , and as the fT4 is non existant, it seems unlikely that this is as simple as just a hyper phase .
"I’ve had two thyroid ultrasounds and both came back normal, is there any other diagnostic test for Hashimoto please? "
They have found confirmed evidence of autoimmune damage to thyroid glands of people with no history of raised TPOab /TGab ( ie , found after removal of gland, during biopsy ) . so yes , it's possible to have autoimmune damage without raised TPOab /TGab (it's pretty unusual though)
sometimes they might be able to see evidence of typical autoimmune damage on ultrasound , but probably not until it's quite advanced ..... so your negative TPOab and clear ultrasounds make autoimmune damage less likely , but not impossible.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
i was just reading this , until my brain melted... jnm.snmjournals.org/content... UNCOMMON CAUSES OF THYROTOXICOSIS WITH INCREASED UPTAKE OF RADIOIODINE ...
it discuss causes without increased uptake further down , but i didn't see any explanations for your issues.
Thank you Tattybogle. I really appreciate your help with this and time to list results. I didn’t ever get the TSI result so am assuming it didn’t show anything but I’ll check.
The link is interesting and frightening, I’m concerned the thing in my liver is connected but can’t see liver mentioned yet - I’m halfway through it. I did a low iodine diet for two months and didn’t get any benefit other than it confirmed my passionate dislike of kale! I was tested for celiac but wasn’t told, I eat low carb so not sure if the results are reliable.
I don’t have the results of my uptake test but it was definitely a low result.
I’ve split the Carbimazole into 4 doses so reduced to 20mg per day. Hopefully this will ease symptoms whilst I wait for what’s next.
You have had some good replies from PurpleNails and pennyannie and tattybogle . So my contribution is pretty insignificant.
But I am wondering how you are taking the Carbimazole. All at once - or split?
helvella - Splitting Carbimazole Doses
A short discussion about Carbimazole primarily focussed on splitting doses but containing other information which may be helpful to anyone taking, or considering, Carbimazole.
Thanks Helvella, that’s a good point, thank you. I’ve been taking the full dose every morning so will look into splitting the dose. Thanks for the blog link, this might be an Avenue into better tolerating the med.
Our situations are quite different- so, I'm not suggesting you do the same but I stopped taking Carbimazole after just a few months, against the advice of my Endo.
As someone who used to roll my eyes about those who don't follow the advice of the 'professionals', I now think it's incredibly important to take charge of your own health - particularly in areas such as the thyroid, where research is still limited.
My antibodies were over 200, and my FT3 above 30, which dropped below range within a few months of taking Carbimazole.
I stopped taking Carbimazole and slowly weaned myself off Propranolol.
I was diagnosed with Graves but my antibodies indicated Hashimotos and the forum told me it's likely to be Hashimotos having a hyper swing. There's very little solid information to be found about this but it dropped so quickly, I was inclined to belive it. I had most of the symptoms of Hashimotos.
I have now been off Carbimazole and Propranolol for well over 6 months and my thyroid has remained stable for now. I feel better than I have in years and am left fighting Thyroid Eye Disease only.
Get your vitamins in range. I belive this has helped drastically. I also have continued to be monitored by the Endo and get a full thyroid panel done every 3 months.
Unfortunately thyroid care isn't anywhere near as good as it should be and I think to some extent, you have to pick what advice works for you because none if it is 100% certain yet.
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