I am almost 8 months into Carbimazole (20mg twice a day, same dose since July and Propanalol 3 times a day) and not achieving anything close to control so have been living thyrotoxic for at least 10 months, and probably more like a year. Swapping to PTU was briefly discussed last week, but when I asked (what I thought were legitimate) questions, I was accused of refusing to swap and the option removed. In true gaslighting behaviour, the letter to my GP says the decision to stay on Carbimazole was jointly made by myself and the consultant, who is 'more than happy for me to contact him at any point to revisit the conversation', would review in 8 weeks. No mention of him ordering the wrong blood tests last week or the fact that my next appointment is 6 months away. I can't anymore! My GP is saying her hands are tied so I need to find a solution whilst I wait for PALS to respond.
I have a tooth extraction I desperately need doing - but the risks of sedation or GA are too high at the moment and no-one will touch it until I get some kind of control over my thyroid so as well as hyperthyroid, I have tooth pain on a daily basis, sinus pain from TED and am generally miserable.
I really need to get some control over this craziness.
The Endo Nurse has suggested the Carbimazole as a single daily dose - I'm not really clear how this might help as surely a split dose means constant (ish) level whereas a single dose will be a peak and trough?
Any other thoughts on switching or not? I know PTU is way harder on the liver - I've been OK this far on liver tests but have been borderline neutropenic over the summer.
I am worried about side effects - struggled to get to the current dose of Carbimazole so titrating that down and then PTU up doesn't fill me with joy. I have several autoimmune conditions and am also therefore worried about the lupus syndrome risk with PTU.
The consultant only really wanted to say that PTU can go to a much higher dose than Carbimazole.
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The Endo appt went ahead without recent blood tests in the end. It was a short (pointless) appointment. I had bloods taken after the appointment - I'll pop the results below. But the Endo 'forgot' to request T3.......
I knew there was an increase possible in Carbimazole - but the Endo didn't really have this as an option. I have struggled with titrating up to the 40mg I am currently taking, so I didn't push an increase! Ranges remain the same throughout.
April 2024 (10mg Carbimazole twice a day) - TSH <0.05, T4 - 30
June 2024 (10mg Carbimazole twice a day) - TSH <0.05, T4- 39, T3 -24 Carbimazole increased to 20mg twice a day
August 2024 - (20mg Carbimazole twice a day) - TSH <0.05, T4 - 26, T3 - (can't find it)
October 2024 - (20mg Carbimazole twice a day) - TSH <0.05, T4- 25, T3 - not requested
I am not expecting TSH to move yet, so let's ignore it for now. T4 wise the Carbimazole looked like it was going to be effective, then clearly wasn't. The increased dose looked again like it would be effective, but in the last 10 weeks T4 has only dropped by 1. I'm half expecting T4 to increase again by next bloods given the pattern seems to be that Carbimazole is initially effective and then my thyroid seems to adapt or override it.
I have a Medichecks kit here for whenever it might be needed - just don't see the point right now given that bloods last week showed such little change in the last 10 weeks. It's not a full picture, though, without the T3.
I have no idea why the endo nurse made the one dose a day suggestion. None at all.
(In an ideal world, you would have been able to ask why - in detail - with the expectation of a properly argued and referenced reply. Of course, we know that isn't going to happen.)
Adults
The initial dose is in the range 20 to 60mg, taken as two to three divided doses. The
dose should be titrated against thyroid function until the patient is euthyroid in order
to reduce the risk of over-treatment and resultant hypothyroidism.
Likewise I have no idea of the logic in going to one daily dose - the Endo suggested it as well. The letter to my GP says 'recommended to try 1 daily dose instead of 2 split doses to see if this helps with tolerability......' which is utter nonsense to me. I've 'tolerated' the split dose for weeks now without too many issues, although I did struggle to begin with. Surely whacking the whole lot in my system at once will only INCREASE the risk of side effects, not decrease it! And then there's the whole half-life discussion of Carbimazole, and one daily dose giving my thyroid the opportunity to get round the antithyroid drugs when they are lowest in my system - which, given how clever/stubborn/resistant my thyroid appears to be, is a strong possibility.
Drs consider Carbimazole 1st option, because it’s considered safer / less complications with liver. Carbimazole is also thought to work more rapidly, although PTU can have a greater action on lowering FT3 levels.
PTU is an older drug & chemically different, it’s only offered in 50mg pills. You would need to take 10x the equivalent in mg to have same affect as carbimazole offers. So 40mg carbimazole would equate to 400mg PTU - or 8 x 50mg daily pills.
Drs assume patients find counting out & taking so many pills inconvenient & confusing and prefer to say carbimazole is simpler (for patients) to take a single pill, 1x a day & carbimazole is available in a greater variety of doses.
I suspect though Doctors aren’t used to using PTU as much as carbimazole, & the thought of calculating & adjusting the correct amount worries them.
You also have to question if the issue is really that carbimazole does not work or it is that doctors aren’t monitoring & adjusting doses appropriately?
If your condition is particularly unpredictable you should be switched to block & replace.
What do your instincts say about choosing PTU or Carbimazole? Doctors tend to assume you will go with their recommendation. Although what happened with you sounds particularly unhelpful.
Have you seen the leaflet about antithyroid medication by British Thyroid Foundation? Hospital departments often hand them out. It’s useful to be familiar with the information in them as this it what doctors should be using as a guide to explain treatment options to you.
I have seen the leaflet before - but it was good to re-read and remind myself.
The Endo really pushed the fact that PTU has a higher daily limit so there was more room to go to 1200mg/day which I guess is the equivalent of 120mg Carbimazole so essentially double the maximum.
I asked about Block and Replace - mostly because I wanted to understand it as an option given that at 40mg/day Carbimazole, I've not achieved control the usual timescales, let alone complete block. But I was told that 'it's not an option' where I live. I've gotten hold of a copy of the local prescribing recommendations, so I will see what that actually says rather than what I've been told.
I don't know that I feel particularly strongly either way about Carbimazole v PTU. Clearly risks to both, but there are also risks to being thyrotoxic for a significant period of time as well as the fact that my eyes are affected and I can't get dental treatment etc. My main worry was the titration off Carbimazole and onto PTU given that I have struggled with Carbimazole although at the moment things have settled (touch wood), and the risk of Lupus like syndrome with PTU which doesn't appear to be a known risk with Carbimazole. I fully understand that side effects are rare and that the risk of lupus like syndromes is rarer still - but I guess the fact that most people tolerate Carbimazole with very little issue whereas I have struggled, and the fact that I already have multiple autoimmune conditions just made me question if my risk was higher than usual.
It may of course be insignificant to switch, with no side effects at all. The unpredictability of it makes it harder to decide!
Were you able to talk of trying Block & Replace treatment :
In this way your dose of the AT drug is increased to fully block your thyroid hormone production BUT a measured dose of T4 thyroid hormone - is prescribed so your T3/T4 don't fall straight through the ranges with you then dealing with the equally disabling symptoms of hypothyroidism.
I couldn't understand why blood tests were not required for this first appointment - without them - how can anyone monitor your progress - and adjust the drugs effectively ?
Was there talk of a thyroidectomy and skipping the AT drug treatment regime ?
I'm at a loss to say anything sensible :
I hope you get somewhere with the PM you posted the other day.
Block and Replace is seemingly not offered where I live..... I am going to look into this statement a bit more before believing it is true!
Similarly, I was told that definitive treatment would only be considered if I relapsed. Which is an interesting comment given that 8 months in I am yet to get control..... If/when I get to remission, I think the likelihood of relapse will be high. My TRAb was very high and this battle to get control points to a higher risk of relapse.
I am not sure if it's a lack of resources, pressure on the system or general indifference that makes it feel like monitoring progress and adjusting medication is not a priority.
I've emailed the Department Secretary and copied in the Director to request a change of consultant so maybe that will be the trigger for better outcomes.
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