When I first started taking Carbimazole, I was on 40mg twice a day. After 4 days, I developed a sore throat and cold-like symptoms so I stopped the meds and went for a blood test for a full blood count. The results showed I had a lower White Blood Cell count so I was booked in for another test 2 days later. I was not on the Carbimazole for this test and it showed my WBC had improved.
My Endo rang me and changed my prescription of Carbimazole to 5mg twice a day with blood tests once a week. If the blood test returned a normal WBC I was to up my prescription by 10mg a week until I was on the desired 40mg twice a day.
After a week of taking the 5mg twice a day, I felt fine and went for the scheduled blood test. My results showed, to my surprise, that my WBC was lowered again so I was booked in for another blood test a week later. When I went in for this blood test, I felt very lethargic and the nurse even commented that I looked "washed out". This was on Wednesday afternoon and by Friday my blood test results weren't back. I am still taking the Carbimazole at 5mg twice a day, but since yesterday morning I have felt like I am coming down with a cold. I have a terrible headache, I feel fuzzy, and I have a bit of a runny nose. I don't have a sore throat though so I'm not sure what to do, should I stop taking the Carbimazole and hope my blood test results are ready tomorrow? Or do I go for a blood test today?
It's ridiculous how long I have to wait for my blood test results at my local gp.
Has anyone else been in this situation? Any advice would be greatly appreciated!
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Ashley1985
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Most people at risk of agranulocytosis or neutropenia should already be aware of signs to look out for, and will have been told what to do if they experience them.
For example, if you have been having chemotherapy, your cancer care team may have given you a telephone number you can call if you experience any problems, such as a high temperature.
If you know you are at risk of these white blood cell deficiencies and you start to feel unwell, it's important to contact your doctor or care team immediately.
Sepsis is a medical emergency and should be assessed by a doctor in hospital as soon as possible so appropriate treatment can be started quickly.
Please take particular notice of the word immediately.
In case it isn't clear, agranulocytosisis a recognised side effect of carbimazole in some people.
The Summary of Product Characteristics for Carbimazole also uses the same word:
4.4 Special warnings and precautions for use
Bone marrow depression including neutropenia, eosinophilia, leucopenia and agranulocytosis has been reported. Fatalities with carbimazole-induced agranulocytosis have been reported.
Rare cases of pancytopenia/aplastic anaemia and isolated thrombocytopenia have also been reported. Additionally, very rare cases of haemolytic anaemia have been reported.
Patients should always be warned about the onset of sore throats, bruising or bleeding, mouth ulcers, fever and malaise and should be instructed to stop the drug and to seek medical advice immediately. In such patients, white blood cell counts should be performed immediately, particularly where there is any clinical evidence of infection.
Following the onset of any signs and symptoms of hepatic disorder (pain in the upper abdomen, anorexia, general pruritus) in patients, the drug should be stopped and liver function tests performed immediately. Early withdrawal of the drug will increase the chance of complete recovery.
Carbimazole tablets should be used with caution in patients with mild-moderate hepatic insufficiency. If abnormal liver function is discovered, the treatment should be stopped. The half-life may be prolonged due to the liver disorder.
Carbimazole should be stopped temporarily at the time of administration of radio-iodine (to avoid thyroid crisis).
Patients unable to comply with the instructions for use or who cannot be monitored regularly should not be treated with carbimazole.
Regular full blood count checks should be carried out in patients who may be confused or have a poor memory.
Precaution should be taken in patients with intrathoracic goitre, which may worsen during initial treatment with carbimazole. Tracheal obstruction may occur due to intrathoracic goitre.
The use of carbimazole in non-pregnant women of childbearing potential should be based on individual risk/benefit assessment (see section 4.6).
There is a risk of cross-allergy between carbimazole, the active metabolite thiamazole (methimazole) and propylthiouracil.
Carbimazole contains lactose
Patients with rare hereditary problems of galactose intolerance, the Lapp lactase deficiency or glucose-galactose malabsorption should not take this medicine.
DONT KNOW WHATS GOING ON BUT THIS POST WAS NOT MADE BY FRUITANDNUTCASE.
Shortly after I started carbimazole 40mcg a day I developed a slightly sore throat, I didn't have mouth ulcers or any of the other things mentioned on the patient information leaflet - just slight sore throat and swollen gland.
I didn't feel at all ill either and I felt that from the symptoms listed if it had been agranulocytosis I would probably have been feeling pretty ill, pretty quickly - BUT I have no medical background, that is only what I felt about it. The information in the leaflet and the consequences are definitely pretty scary.
So I don't know what I'd do but if carbimazole seems to be lowering your WBC every time you try to increase the dose (and you have got test results that indicate that it is) then what about contacting your endo via his / her secretary and asking to try PTU which (I think) is the same sort of anti thyroid medicine.
In my case as it was coming up to the Christmas break, I rang up and had a WBC test done just to be on the safe side. The results were fine. Next time I had another sore throat a while afterwards, and again, I felt quite well, I got a same day appointment to be on the safe side and after a discussion with the practice nurse and a doctor it was decided to work on a 'wait and see' basis which I did and I was fine.
I see it is nine hours since you posted so hopefully you have been able to resolve your problem.
PS - I meant to say but missed out and can't get back to edit - I'd stop taking it until you have spoken someone either your doctor or your endo. no point running this - if you're on carbimazole you are probably feeling awful, y don't want t end up feeling worse.
After the Endo put my carbimazole up from 2 to 3 x 5mg tabs a day, I started having aches and pains, night cramps and then a high temperature. I phoned my GP practice (I was on holiday at the time) and the Dr said stop taking Carbimazole and go to your nearest A&E IMMEDIATELY. I did that and they discovered that my WBC count was slightly down (results were given straight away) so I kept off Carbimazole. My temperature continued to rise every night for the next 5 days - also extreme night sweats and a sore throat; then things improved quite rapidly.
However after about 10 days, being off carbimazole gave me hyper symptoms that I hadn't had before - in particular raging insomnia (I didn't mind this too much, since I had so much manic energy by day that I was able to get lots done). GP told me to re-introduce Carbimazole gradually, 5 mg a day and then 10. So that's what I'm on now. Have also (following Susan Blum's book) eliminated dairy and gluten from my diet. Feeling (and sleeping) fairly well. Seeing Endo this week so will find out how things stand. (Whatever happens I'm determined NEVER to take more than 10mg of carb. per day since that seems to be all I can tolerate).
It usually seems to take about a week for blood test results to reach one's endo/GP, so listen to your body in the meantime. Some people seem to be able to tolerate Carbimazole better than others, and I think that (in terms of TSH etc) 'normal' must be different for different people (I wish all health professionals recognised this....)
Thanks for your reply! I went in for a blood test today, turns out my results from last week showed a lower WBC again. I don't think I am suited to Carbimazole, I was on 10mg a day and every time I've been on it, it has showed a lowered WBC. I am waiting for my results to come back tomorrow to see what they're like now. I felt awful over the weekend but now I feel better. I will ring my Endo tomorrow with my results. I hope everything goes ok when you see your Endo
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