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Help endo insists i stay on carbimazole 5mg- does he really know what he is talking about?

Hi all i seem to be having abit of a nightmare lately as regards to my results done on the 1st dec.

My endo's secretary has rang today to say endo wants me to keep taking my 5mg carbimazole which i have been on for around 5 weeks now up until 4 days ago when i reduced myself to 3.75mgs and still feel rubbish on but readings on dec 1st were

Tsh 5.27 lab 0.30 4.20

Ft3 4.4 lab 3.1 6.8

Ft4 12.8 lab 12.0 22.00

He is well aware of these results but my concern is the tsh its just going to keep going up, am i right he us just looking at the frees and turning a blind eye to tsh saying its fine when its not as i feel horrid, would prefer for my frees to be halfway through and my tsh more suppressed

, it does state on my blood copy that patients tsh is rising with carbimazole!!

Thanks guys.😊

7 Replies


TSH is rising because FT4 and FT3 are low. TSH doesn't make you feel anything, it is high FT4 and FT3 which make you feel hyperthyroid and low FT4 and FT3 which make you feel hypothyroid. The dose reduction you made 4 days ago should raise FT4 and FT3 higher and lower TSH.


Hi clutter my tsh is rising but to feel much better it does need to be lower? If i carry on 5mgs my frees will become higher and my tsh lowers is that correct? As it stands my tsh is above range aswell. Dont know what to do as endo wants me on 5mgs still. Sorry bit confused as whats what.



TSH rises because FT4 and FT3 drop. Reducing dose to 3.75mg may stop FT4 and FT3 dropping and TSH rising. Only way to be sure is to wait and see.

Your endo can only advise you. He can't force you to remain on 5mg.


3.75 mg of Carbimazole ? Given the tablets come in 20mg or 5mg, you must be spending a lot of time with the pill cutter, and I wonder if you are getting a consistent dose ?

I’m rubbish at it myself, I currently have a massive bottle of 20mg tabs which I need to cut in half each day, and realised a long time ago that I need to take the second half of the same pill the next day to make sure I’m not taking several small “halves” in one go....then there is all the powder and crumbs in the bottom of the cutter !

I can’t remember - are you on Levo as well ? Presumably yes, or your thyroid numbers will continue to head downwards


No just on carbi, endo changed his mind about block and replace months ago , he wants me to stay on just carbi 5mgs but i lowered it myself 3 days ago and have just been cutting it with a knife but have got a pill cutter today.we have no choice to cut them as the pills only do a lower dose in 5mgs. I cut the tablet in half and then cut other half in quarters and bin the one quarter, i think it is something like 3.75 lol but it probably equals something else?

I think my endo is useless and have asked to see someone else on the 2nd. What dose do you take?


If you lower your dose of carbimazole then TSH will drop but you need to keep in mind that any dose increase or decrease will take around 4 to 6 weeks to take full effect


Thanks karen yes i am aware of the dosage change and the time period. Just wish it would hapoen more quickly but nothing is ever quick with thyroids.x😊


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