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Thyroid UK
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Cabrimazole over-prescribed? Antibody query

Hi this is my first post. I was diagnosed with Hyperthroidism in October and after seeing an Endo was put on 20mg Cabrimazole. In 4 weeks FT3/FT4 were both in range, TSH still fully suppressed. Dose was then increased to 30mg. After another 6 weeks FT4/FT3 both now on lower end of range FT4 11.2 (9.0-19.0), FT3 4.0 (2.6-5.7) TSH 1.04 (0.4-5.0). I expected the dose to be reduced but was told I would need to stay on 30mg for the next 12 months which contradicts everything I’ve read. I’ve questioned the Endo 3 times regarding my concern over the dose because taking it makes me feel so terrible. So 2 weeks ago I decided to drop the dose to 10mg and see what happens. I've just had a Blue Horizon blood test done and FT4 is now 13.0 (12-22) FT3 is 4.63 (3.1-6.8) TSH now 2.57 (0.27-4.2) so T3/T4 getting even lower, TSH on the rise. T4 Total 81.4 (66-181).

I’m thinking I need to stop taking the Cabrimazole altogether until my FT3/FT4 levels are back to normal (I've read on here that FT4 should be around 70% of range) - it’s pushing me right to the bottom end of the range and I’ve had lots of the symptoms of being underactive.

I’ve been told I have Graves due to:

Thyroidperoxidase a/b 69.1 (<34)

Thyroglobulin a/b 483 (<115)

TRAB 2.7 (<0.4).

I’ve also just had vitamins tested for:

hs-CRP 0.57 (<5.0)

Ferritin 173.0 (30-400)

Vitamin D (25 OH) 41 (insufficient 25-50)

Vitamin B12 253 (insufficient 145-250)

Serum Folate 31.6 (8.83-60.8)

After a few weeks of starting on the Cabrimazole I started to feel much better but now I am very low in energy levels all the time.

Any help/guidance would be really appreciated. I don’t feel like the Endo has a clue what he’s doing!!

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Mw2304,

I think it is premature to stop Carbimazole when you've only been taking it since October. Patients are usually expected to stay on Carbimazole for 12-18 months to regulate thyroid and wean off towards the end.

It does appear you were overmedicated on 30mg but it may have been better to have reduced to 20mg and retest after 4 weeks. I would certainly retest 4 weeks after dropping to 10mg because if FT4 and FT3 are rising quickly you will need to increase dose. If you are going to self medicate make adjustments small, say 5mg doses.

Thyroid peroxidase and thyroglobulin antibodies are positive for Hashimoto's and TRab is positive for Graves so you have Graves and Hashimoto's in tandem.

thyroiduk.org.uk/tuk/about_...

There is no cure for Graves and Hashimoto's but many people have found that 100% gluten-free diet is helpful in reducing Hashi antibodies in time.

chriskresser.com/the-gluten...

thyroiduk.org.uk/tuk/about_...

CRP is an inflammation marker so the low result is good.

Ferritin and folate levels are good.

Is that all there is for the B12 range? 253 is low. If you have symptoms in b12deficiency.info/signs-an... go to healthunlocked.com/pasoc for advice as they're the experts on B12 deficientcy. If you aren't symptomatic supplement 1,000mcg methylcobalamin to raise B12.

VitD 41 is insufficient. My sister's GP prescribed 2 x 20,000iu per week when her vitD was 40. Your GP should refer to local guidelines or the cks.nice.org.uk/vitamin-d-d... Do NOT accept a prescription for 800iu which is a maintenance dose prescribed after vitD is replete >75. If your GP won't prescribe buy vitamin D3 and supplement 10,000iu D3 daily x 6 weeks and then reduce to 5,000iu daily and retest in May.

If you buy on Amazon please use the affiliate link healthunlocked.com/thyroidu...

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Hi Clutter, thanks for the info. I'm really looking to get T3/T4 levels back to normal as soon as possible to stop the symptoms over being underactive asap, hence I was thinking about stopping to take the meds short term to help this happen. Then reintroduce at a much smaller dose until remission is achieved. Sorry I don't think I made that clear from my post. I've also got a second opinion with another consultant but that's not for another 4 weeks. There's no way I can wait until then to take action if I'm already over medicated. I'll have a good look at the links you've given, thanks for your help.

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Stopping the meds now may affect your long term remission prospects. It is better to reduce the dose gradually and to keep taking it until you are able to come off them completely. The meds can help lower thyroid antibodies. Your FT3 is fine at the moment, it is mid range and not at the lower end of its range.

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Hello mw,

I can totally understand your questioning the idea of taking the med for a whole year when you are already in normal ranges. Even when you dropped it down it's still in normal ranges.

Is your dr hoping to make your thyroid underactive? Are you eventually getting RAI? Or are you just wanting to get in remission? Hope you can get some clarity on what your dr has for an end goal on your thyroid, and find out if that matches what you want.

We are not doctors so we really cannot comment on specifics, but I can tell you when I get my results in ranges like you have, my dr takes me off the med. I have hyperthyroid and Grave's Auto-immune disease.

In my case I want to be in remission, I do not want to get RAI or go to hypo. Best wishes to you, I know how frustrating this is, believe me! Sounds like you just need to make sure your goal matches your endos and if they don't, that could explain the circumstance you have.

Thank you. Red

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Hi Redeyes2

I can't imagine that any of us want to take antithyroids for longer than necessary. However, it seems that receiving therapy for 12-18 months provides the best chance of achieving remission ncbi.nlm.nih.gov/pmc/articl... The odd thing here is that the dose is still quite high/no levo has been introduced, when Mw2304's levels appear to be well within range (and on the way down !)

In the UK (I think you are in the US?), we usually get at least one crack at achieving remission with antithyroids before they even consider RAI, so I doubt that Mw2304's endo will be considering that option yet, and he should be aiming for remission. I believe in the US, they are more likely to suggest RAI at an earlier stage ?

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Hi Valarian, thanks for your reply. I am in the UK but RAI has never been discussed, neither has block and replace or titration. My consultant was very clear when he said that I would need to be on the same 30mg dose for the next 12 months just to aim for remission!

Sorry I don't think I made that clear from my post but I'm really looking to get T3/T4 levels back to normal as soon as possible to stop the symptoms of being underactive asap, hence I was thinking about stopping to take the meds short term to help this happen. Then reintroduce at a much smaller dose until remission is achieved. I've also got a second opinion with another consultant but that's not for another 4 weeks. There's no way I can wait until then to take action if I'm already over medicated. Thanks for the tip about adding to the title.

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The problem is, your thyroid may not play ball !

We're all different, but....my endo reduced my Carbimazole because I was below range at my regular test, and by the next test I was over again. I never went below 10mg. They increased the dose again (to 20mg), but six weeks later, my FT3 was still over range. It isn't an exact science, but if you stop taking it altogether, there is a risk that you could end up back at square 1.

The 30mg dose for 12 months with no levo does sound odd....but so does the idea of stopping it altogether after only 10 weeks.

Have you always felt bad on carbimazole, or only since your thyroid levels reduced ?

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PS do you have a Fitbit, Apple watch, or similar ? It may not work for everyone, but I've fond my heart rate to be a fairly reliable indicator of my thyroid levels

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Yes it's always made me feel awful, I have to take it before bed so when it kicks in I'm already asleep. For the last 8 weeks I've been really conscious that my mood has been changing for the worse. I've been suffering from a real lack of drive which I've never had in my life. I'm 43 and always been very well motivated but I feel the life is being sucked out of me. I didn't take the meds for the first time last night and I feel great now compared to normal, my head is lots clearer. I know I'll need to continue taking them but just want to try and get the levels back to being higher up in the range as quickly as possible.

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Hi Redeyes, RAI has never been discussed, neither has block and replace or titration. My consultant was very clear when he said that I would need to be on the same 30mg dose for the next 12 months just to aim for remission!

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Hi mw2304 , and welcome !

The elevated TRAb is the indicator for Graves'. Your TPOab is also elevated, which can be indicative of another (generally hypO rather than hypER) autoimmune disease, but more than 50% of Graves' patients also have these antibodies. With Hashi's, I think the level of TPOab would usually be higher than this. If you add "antibodies query" to the title of the post, hopefully someone will come along who knows more about this topic that I do !

It is usual for those of us with Graves' to remain on Carbimazole for 12-18 months, as this is supposed to give us the best chance of achieving remission. Normally, once in a stable "euthyroid" (ie within range) state, either the dose is gradually reduced, or the level of Carbimazole is maintained, but supplemented with levothyroxine, a thyroid replacement.

You aren't hypo at the moment - (and in fact, even if your levels were below range, you would be over-medicated rather than truly hypo, although the symptoms are the same).

I would be wary of stopping the Carbimazole altogether, because doing so may reduce your chances of achieving remission. Although GPs know less about the thyroid than endos, I wonder whether it would be worth making an appointment to see your GP, and explaining your concerns ? They might be able to get an explanation out of the endo, even if you can't. However, note that your GP should not alter your carbimazole does while you are under an endo (although they could certainly query it). Whether you talk to your endo or your GP next, I think you will need to come clean on the fact that you have reduced the dose and had new tests done, as they shouldn't be looking at one set of results in isolation, and not knowing that you have reduced your carbimazole before your next official tests may lead them to draw the wrong conclusions.

Just a word of warning on symptoms. When we are first diagnosed as hyper, most of us feel absolutely awful. After a few weeks on carbi, we reach a point where we feel miles better, However, we may find that we swing from feeling really bright and active, to conking out completely after a period of (hyper !) activity. Friends and family may tell us that we are talking very fast, and we may find that our mouths struggle to keep up with our superfast brains, and we stumble over words. Then, as our thyroid levels come within range, things can feel very flat. I'm not saying that you haven't been experiencing "hypo" type symptoms, just that there is a stage of being hyper, just a bit above the normal ranges, which can feel pretty seductive, and normal ranges may be a bit disappointing after this !

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Hey,

I can totally sympathise with you I have had a few people say I am over medicated and my aim is the same I’m trying to get my tsh down and my ft4 up.

I have felt rotten for the last 5 months even though my thyroid is in ‘normal range’ and it makes you feel like You don’t even recognise your life.

I must say as I have decreased I can feel alittle but more of me coming back and feeling better but it’s a bumpy road.

I was so active and motivated I’m now off work and friends with my sofa!! But after all my research I want to give myself the best possible chance of remission....so carbimazole it is!!

I would carry on with the carbimazole even if you do drop the dose and call your endocrinologist secretary and ask for a telephone consultation with another endo (it’s quicker than a face to face appt) There are a lot of side effects to contend with with this medication some people are absolutely fine (lucky things) I hope it all settles for you 😊

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