I have ben told that Carbimazole is a drug that 'can' cause your white blood cell count to reduce and so long -term 'can' affect the immune system - causing the condition Agranulocytosis. It probably depends on a number of factors - how much you are taking on a daily basis/age/other health issues/how well you are generally. I have Graves disease and been on varying doses of Carbimazole for the last 18 months from 5 to 10 - 30 - 15 - and currently 20mg. I have been looking into this issue of effect on white blood cell count. My endocrinologist is now talking about surgery as they can't seem to get the thyroid to stabilise but I am going to resist this!.
From what I've read Agranulocytosis is a well-recognized but rare and life-threatening. side effect of carbimazole therapy, and 'usually' occurs within the first 3 months of treatment. It's a rare condition in which your bone marrow doesn’t make enough of a certain type of white cell, most often neutrophils (which make up the largest percentage of white blood cells in your body and are a critical part of your body’s immune system).
Having regular blood tests to check thyroid levels should mean that this is monitored, although whether they also check white blood cell count is another matter!
I would be interested in asking everyone who is taking Carbimazole how long they have been on the drug, and if long-term what doses are they are on, and what side effects they have.
Tags: #Carbimazole #Agranulocytosis #surgery
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WestBurrafirth
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I came out in a rash when I took Carbimazole so I took PTU which is an older trusted drug. I am now on my second remission so I am taking nothing at the moment. You can read my story on my profile page. Just to add I know someone who has taken it for over 10 years and is ok as long as she has regular blood tests.
Thank you for your reply. I also had an allergic response - hives (Uticaria) and take antihistamine tables to control this. Was taking one a day, now and since giving up gluten and reducing eating histamine-rich foods I take one a few days and this seems to control it.
Members who have the same condition as you, will respond when they read your post.
Hi, if you would like to add a short history of your thyroid journey into your Profile it means members can read it without you answering too often. We just click on a member's name and, hopefully, their history, so far, will be stated.
I have just read your history and, like lots of others on this forum, you've had a journey.
It seems to be 'trial and error' initially as we haven't a clue about dysfunctions of the thyroid gland until ours goes.
Many of us eventually realise that few doctors have sufficient knowledge in diagnosing/treating patients. Before blood tests were introduced we were given (according to our clinical symptoms) a trial of NDT (natural dessicated thyroid hormones - the original that saved millions of lives from 1892 onwards.
Mine phoned me to reassure me that all my results were fine (23 of them) until I requested a print-out and the TSH was 100. I then found Thyroiduk and then began a way forward. TSH is below 1 now.
Hi,
I've been on Carbimazole since November 2018, doses varied between 5mg and 20mg, currently 10mg. I was on 20mg from Aug 2019 -Jan 2020 when my levels plummeted (FT4 below range, FT3 low in range, TSH 40 Range 0.5-4.4). I was taken off Carbi completely until mid-Feb when my levels crept back up and I was put back on 10mg. No side-effects. Hope this helps.
Diagnosed Graves and TED about 4 years ago . At the moment taking 5mg. Carbimazole and 50mcg. Levo and feeling really well although still with double vision. I have agonized over the same questions you are asking. Is Carbimazole safe ? Should I have the thyoidectomy my endo advises ? Will I ever feel healthy again ? I read and I read and noted how I felt with the 12 adjustments to my dose regimen. After years of confusion I now have the confidence that I know better than the docs treating me WHAT IS RIGHT FOR ME and trust my intuition. I said no to thyroidectomy and steroid infusions. I know Carbimazole can cause the side effects you quote but risk is low and even lower on doses under 10mg. that is why I worked with my endo to find the lowest effective dose and although I still hope to achieve remission I am happy to stay on it longterm which evidence shows can help control TED. I know FOR ME if fT3 drops to below half way in range my eyes will start getting congested again. This happened a few weeks ago and I slowly reduced from 10 to 5 mg. Carbimazole which helped. I am not advocating you go against your doctors advice only that YOU are the expert regarding your body. I have 75 years experience studying mine ! It sounds as if you have educated yourself about the disease so you could now trust your instincts
I've had the double vision thing as well - have had a prism put on my glasses to correct the difference in the eye muscles. Have also said no way to steroids and they said I wasn't bad enough anyway. I think that my endocrinologist is thinking too hastily. Good to hear about your experience. Thank you
Yes and I thought I was doing that a few months ago but then he reduced the dose of Carbimazole and then had to increase it. So I am not sure what's going on. What is it replaced with?
If you post your blood results people will have a clearer understanding. However the fact your Carbimazole was reduced probably means you were going hypo which often happens. Have you had your antibodies measured ? If they are still high you are unlikely to be going into remission yet. Therefore in order to stop you going hypo which can worsen your TED you keep taking Carbimazole and add in Levothyroxine. This is called Block and Replace and it works well for me. It needs careful monitoring at the start to find the lowest effective dose.
They don't test antibodies. I can ask next time but whether they will agree to this or not is another matter. I have all my test results which show my T3 T4 TSH levels. Not sure how to post these - I have them as PDFs or JPegs. Do I need to post them somewhere else?
You could do a screen shot of them and start a new thread. I never get my antibodies tested by my GP because I think he doesn't think they are important. I usually have a private blood test so I get a more detailed result instead of just the TSH which is all my surgery does.
Perhaps start with ranges used for TSH fT4 and fT3. Under this write date, what meds you were on and what the values were for above. This might give people the necessary info to constructively comment. Unlikely a GP will do antibody test but endo can. My "good" endo said on my first visit it was essential to see where we were before he treated me.
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