Morning all, I am currently on 10mg of carbimazole per day, and have been taking the 2 x 5mg tabs each morning in one dose.
However, I have noticed that by about 9pm, the heart palpitations return, so then I take a propranolol to settle my heart.
My question is: Would it be better to take just 1x 5mg carbimazole in the morning, and the other one, later on in the evening? Does anyone have any experience of doing it like this? Are there any disadvantages of splitting the dose to twice daily?
I'd be grateful for any input .
Many thanks!
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KittyKat234
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Not only can you split your dose, many would say you absolutely SHOULD split it.
Carbimazole starts to work very soon after taking the tablet(s). It rises rapidly to a peak and then falls quite quickly. By 12 hours, a lot of it has gone. By 24 hours, only a small amount remains.
Its half-life is of the order of 6 hours. If you take 10 milligrams, then 6 hours later you have 5 remaining, at 12 hours, you have 2.5, at 18 there is 1.25, and a full 24 hours later, just 0.625. Effectively, negligible. (This is theoretical. Real world times/remaining could be higher or lower.)
By taking in a single dose, your thyroid can "escape" the effect of the carbimazole and release more thyroid hormone. By splitting, you maintain a more even level.
Patients are often advised to split dose when they start carbimazole, especially if they are severely hyperthyroid, as the effects of escaping its control are particularly significant.
Not splitting your dose will maintain your effective level at between about 10 and 0.7.
Splitting your dose will maintain your effective level at between about 6.6 and 1.66. (Takes two or three days to settle there.)
You can see that while not splitting sees a much higher peak, it also has a far wider range. In particular, it has a lower trough. Splitting maintains your effective dose in a much tighter, more even range.
When the dose is tapered, it is common to end up on 5 or 10 a day and that can (sometimes) be taken in one dose. But experience is king,
From where you are, the only issues with changing to a split dose are:
• It might have a similar effect to a small dose increase;
• You need to remember a second dose;
• Your prescriber should write this in your notes and ensure it is stated as the dosing instructions.
That's great info thanks. I was wondering about its half life, so you've cleared that up for me. It therefore makes sense that my symptoms re appear after about 12 hrs! I'll try the splitting and hopefully it'll give my body a more constant level of the drug. Thanks for the info. Very helpful!
That was my thinking too. If I even out the doseage of Carbim, I might not need the propranalol. Im sure I posted my blood results in my post headed 'Private Blood tests"
Well we are still waiting on confirmation of TSH -Thyroid Receptor antibody for Graves Disease - which is when Carbimazole is then prescribed.
We have a TSH 0.02 and a T3 over range at 10.90 ( range 3.10-6.80 )with no T4 readings and over range TPO antibodies suggesting Hashimoto's which is not medicated with an Anti Thyroid drug - such as Carbimazole.
Graves and Hashimoto's often start off the same way , both are auto immune malfunctions, and why it is important to get the Graves antibody blood test run -
With Graves the T3 and T4 thyroid hormones keep rising higher and higher and why it must be medicated with an AT drug and the thyroid hormone production semi blocked while we wait for your immune system to calm back down again.
With Hashimoto's the T3 and T4 thyroid hormones do not keep rising and fall back down into range by themselves and is not medicated - but you are liable to erratic own thyroid hormone production and ' swings ' in symptoms and eventually you will become hypothyroid and require thyroid hormone replacement.
But what you haven't provided is the Graves Disease antibody blood test :
Graves may be suspected but medical guidelines are followed as proof of Graves is required before the drugs should be dispensed.
This may well have been undertaken from your initial first blood test as laboratories tend to follow ' cascade type ' blood tests - meaning -
First run a TSH - if in range - this maybe as far as the analysis goes :
If TSH is not in range and low suppressed -
run a T4 - if high and out of range -
then run a T3 and if high and out of range -
then run the Graves Disease antibody reading from the same blood sample to rule in or out Graves - as the reason for these high/over range readings :
There is more than 1 reason why your TSH is suppressed - and the TSH the least reliable measure of anything when dealing with a thyroid auto immune disease.
As we have already discussed Graves and Hashimoto's start the same way - all I'm trying o do is establish exactly what's going on - as currently you are being treated for Graves but with a medical diagnosis of Hashimoto's
Ok I see what you are saying now. Those blood results are all my GP has provided. They havent run T4 at all, and the only antibody results given were for the Thyroid peroxidase. The GP actually called me and said it was Graves. What do you suggest I do? I had a further blood test at the hospital but havent had those results back yet. Maybe those results will show the graves Ab test?
Well - I would hope the hospital results will include the Graves antibody reading - if it hasn't been run already :
Do you have access to your medical records and can check back and see exactly what was run initially - as it just seems strange to have a T3 and not a T4 ?
Was the hospital appointment to also discuss treatment options with an endocrinologist or just for bloods and a follow up appointment arranged once the blood tests were back ?
The GP said graves, but after speaking to you, Im not sure how he can have diagnosed that, being as he hasnt run the correct Ab tests! They did say it goes in peaks and troughs so yes 12-18 m was mentioned. Re my T4. Ive paid for private bloods so once I have had the blood taken and analysed, Ill be able to give you a T4 result
Ok then - you might like read around Graves and suggest elaine-moore.com : Elaine has Graves and now a leading authority on this poorly understood and badly treated AI disease - for which there is no known cure -
and for Hashimoto''s - Dr Isabella Wentz is a well respected researcher who has this disease herself and writes as thyroidpharmacist.com
With both diseases you are looking at an immune system malfunction -
and the thyroid is the victim in all this and not the cause.
The most recent research for the treatment of Graves is suggesting the longer the AT drug is used the better the long term outlook for the patient :
Yes I already discovered Elaine moore website, and was told about Isabella Wentz the other day. Since being diagnosed with this thyroid 'Thing" Ive been on a mission to research it. I realise that my thyroid is the victim, and have been taking supplements to treat the body as a whole ( increasing Vit D, K Selenium, etc) and reducing free radicals by way of Reduced Glutathione, increasing short chain fatty acids (Flax seed oil), reducing processed foods amd goitrogens, and trying to decrease TPO Ab by taking cordyceps ( which apparently is a modulator) Lemon Balm for the heart, Nigella Sativa, and also good quality pro biotics (Ive read that thyroid patients have an imbalance between Lacto strains, and Bifido Strains) I'm very fortunate that I work in an independant health food store!!
Aside from all that, just wanna say thanks for your perseverance earlier. If it werent for you, I wouldnt have known about that Graves Ab test- so thankyou! 🙏
Also, this is the first day that I split my dose. The palps came back at about 7pm, which is good really coz I took the first dose at about 8am this morning. I took the 2nd carbimazole at 7pm, but the palps havent subsided yet, so im gonna have to take a propanalol. The aim is to cut that out by way of evening out my carbimazole, but its a work in progress I guess!
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