Hi all,
I’ve just been diagnosed with Graves and I’ve been put on 40mg of carbimazole daily. Everywhere I’ve read speaks of weight gain. Has anyone manage to lose weight or maintain their weight on carbimazole? If so do you have any tips or advice?
I already weigh more than I’d like to do I’m keen not to gain more weigh.
Thank you in advance 
Has GP confirmed Graves’ disease by testing TSI or Trab antibodies
Have you had vitamin D, folate, ferritin and B12 testing too
I’m not sure what testing I’ve had to be honest.. I’ve asked for a copy of my results.
Come back with new post once you get results and ranges
You need TSH, Ft4 , Ft3
Thyroid antibodies
TSI or Trab antibodies tested for Graves’ disease
TPO and TG antibodies for Hashimoto’s (and can be slightly raised with Graves’ disease too)
Hashimoto’s frequently starts with transient hyperthyroid results and symptoms before becoming increasingly hypothyroid
Vitamin D, folate, ferritin and B12
Yes but what I really want to know is about carbimazole and weight gain as I’ve been put on that medication. Thank you for your responses x
Well usually if hyperthyroid you loose weight before starting Carbimazole …..but not always
some people have such a ravenous appetite when hyperthyroid they do gain weight and then stablize when treated
Also being very hyperthyroid can leave you too exhausted to exercise
Thank you I lost about 8lb within 4 weeks. Even brushing my teeth would leave me exhausted.. I’m just really glad there is some testament! X
So you must start Carbimazole…..but levels need retesting frequently
Also read the Warnings leaflet…..if you get sore throat it’s very important to seek medical help immediately as can indicate low white cell count
I’m sorry to carry bad news, but weight gain happens ..there are so many clever people here, they’ll know, but my experience is that it happens :(. Suggesting to go gluten free, maybe sugar free, but don’t drop all carbs and don’t go hungry, dont diet :), keep your meals balanced and read Izabella Wentz books. Good luck!
Hello Princey and welcome to the forum ;
Carbimazole is an anti thyroid drug which blocks your own production of T3 and T4 thyroid hormones and since your thyroid also controls your metabolism and weight there is likely to be some disruption in " normal service " .
First and foremost we need to see your blood test results and ranges for TSH, T3 and T4 plus the antibodies which are over range and positive.
If there is no obvious swelling in the neck and no nodules the 2 main reasons why you have become hyperthyroid are either Graves or Hashimoto's, both auto immune disease which attack the thyroid causing a multitude of symptoms as the thyroid is a major gland and the body's engine.
The only way to initially tell Hashimoto's and Graves apart is through an antibody blood test.
Carbimazole is usually prescribed for Graves Disease and the antibodies unique to this auto immune disease are generally written as a TSI ( a thyroid stimulating ) or as a TR ab ( a thyroid receptor blocking ) number and range.
As you can see with Graves there are stimulating and blocking antibodies and either of these two extremes can be driving your body as they both compete for control of your metabolism so it can be rocky risky business and Graves is considered life threatening if not medicated.
The AT drug blocks your T3 and T4 levels rising any further, acting a bit like a dam blocking any further thyroid hormone production and slowly your T3 and T4 levels should come back down into range, and your symptoms reduce with you feeling more comfortable.
As your levels reduce back down your endocrinologists will likely start titrating down your AT drug so your T3 and T4 levels do not fall too far down the ranges and you start experiencing the equally disabling symptoms of hypothyroidism.
The NHS generally allocate around a 15-18 month window with AT drugs in the hope that within this time period you can find remission from the first phase of Graves disease.
Everyone's journey with Graves seems to be unique to them and probably why it's still seen as a poorly understood and badly treated AI disease.
Your thyroid is the victim in all this and not the cause - the cause is your immune system mistakenly attacking your body and I read and know from my own experience that my Graves is driven by anxiety and stress, and you might like to give this some thought.
When your thyroid isn't functioning well, and your thyroid hormone production erratic it becomes difficult to metabolise and extract essential key nutrients from your food, so we always suggest you get your core strength body vitamins and minerals tested and arrange for ferritin, folate, B12 and vitamin D to be measured
What symptoms are you dealing with, and can you give us more details, apart from the fact that you are worried about your weight.
If you go into the Thyroid UK website, who are the charity who support this forum you will find a list of both hyper and hypo symptoms and it might be of interest to see which camp you think you currently belong in though it does get confusing as some symptoms can sit in both.
I'm with Graves post RAI thyroid ablation in 2005 and now manage lingering Graves, thyroid eye disease and hypothyroidism.
Hi, I lost half a stone before being diagnosed with Graves. Taking Carbimazole slowly returned me to my original weight so no it did not make me put on any extra. I find it strange that if you have Graves you didn't lose weight (but then we are all different). However it makes me question if your diagnosis of Graves is correct and why it is important to know what was tested. Carbimazole can make you very quickly go hypothyroid. You must be closely monitored to avoid this. Going hypo could lead to your weight increasing. Those blood test results are important.
Thank you for taking the time to reply. I lost around 8lb in 4 weeks… I’m trying to get my head around all the new information, I think I have a lot to learn. Thank you
Yes there is so much to learn. It took me about 2 years before I was confident enough to question what Docs were telling me. You have found this forum earlier in your journey than I did which will help. First step - gather all those blood results and keep notes on dose and symptoms - you will find the record invaluable in the future as most of us Graves patients need many adjustments to keep feeling well.
Hi
My MIL had treatment for overactive thyroid, to the surprise of us all as she's always struggled with her weight, s she has type 2 diabetes as well. She had the radioactive pill treatment a few years ago. There are some hyper patients who don't lose weight I believe.
Yes we are all very different and therefore important to learn how AITD specifically affects you and recognise periods of being hypo or hyper although with some symptoms overlapping that's sometimes difficult.
When I was first diagnosed with being hyperactive in 1981 I lost weight very quickly , after giving birth to my second baby and found myself having a partial thyroidectomy 5 months later, then onto carbimazole a few months later, which I remained on for around 4 years. Everything was good until approximately 6 years ago when it started again but I put weight on which confused me, the endocrinologist told me that it does happen sometimes. Since then I have had another partial thyroidectomy, more carbimazole and eventually RAI, I’m now on thyroxine and the weight is on and definitely not going anywhere.
Every individual is different I gained weight whist hyper & lost weight while taking carbimazole.
As weight loss is common when hyper, regaining it once on carbimazole is expected.
We are advised to be careful as we have become accustomed to larger apatite.
If you are not monitored well by your doctors may lead to hypothyroid levels. The medication needs to be adjusted to prevent it. Having hypo level can lead to weight gain. Doctors tend to freak at the hint of hyper like to bring down levels quickly & keep them there.
I had hyper levels for many years from a nodule, so not as high as seen with Graves but over a much longer time. I have a lot of weight gain as my appetite was uncontrollable. Once on carbimazole and thyroid levels below mid range I did lose weight.
Hyper is considered dangerous, hypo less so by doctors. So it’s important to obtain result and ensure the right things are being checked.
How much carbimazole are you taking & how long? You should be retested no later than 6 weeks after starting medication.
Thank you for your response I’m on 40mg daily - I don’t know how long but I think I get retested in 4/6 weeks.
40mg is a normal starting dose for high levels (the maximum is 60mg).
When retested, the aim is your levels will be in range & the dose can be reduced to keep the levels even & not too low.
For example I began on 20mg (10mg x2 per day) my appointment got delayed & I was retested until 8 weeks later & I was approaching hypo levels. The dose was half. I then fluctuated between 10mg dose & 15mg dose every other 6 weeks. I currently take 10 / 5mg alternate days.
many people (but not all) loose a lot of weight when they are hyperthyroid. This is due to too much thyroid hormone... (your '0ver 70' fT4 result ).. making their metabolism run too fast.
Carbimazole itself isn't the thing that makes these people then put weight on.. it is that the carbimazole reduces their 'too high' thyroid hormone levels... and if it reduces them too much... then they put weight on.. due to too low thyroid hormone levels causing their metabolism to run too slow.
sometimes they would just put the weigh back on that they lost when their metabolism was running too fast.
The reason we keep asking about test results .. (particulary TRab antibodies to confirm Graves ) is that some people are prescribed carbimazole before they have had diagnosis of 'graves' confirmed by TRab .
In these cases .. if it turns out that they didn't actually have graves , and their hyperthyroidism was not caused by 'continuous overproduction of thyroid hormone', but by the early stage of autoimmune hyPOthyroidism , which has a temporary period of 'too much thyroid hormone' that will go down by itself naturally and they will end up with 'too little' ..... if you give those people carbimazole.. then they will end up with 'too little' very quickly .. and if this is not noticed due to blood test not being done frequently enough... then yes they would be at risk of putting weight on .
So this is why we keep asking if they've done the blood test to confirm the cause of your hyperthroidism.
But the main priority at the moment is to get your thyroid hormone levels down to deal with the symptoms they are causing.
Thank you so much for your response, it is so helpful. The hospital said it was Graves but I’m not aware that they did a blood test to confirm. I will post a copy of my results as soon as I have access. Thank you again
To be honest ( assuming we are correct in our assumption of the 'over 70' result being fT4 ) ...... it is fairly likely that you do have graves .
graves often gives fT4 levels that are 3 or 4 times over the 'top of the range' , and over 70 would fit with that since most fT4 ranges go up to about 18 ish.
Whereas the transient high fT4 levels that come with early autoimmune hypo are usually not that high.. maybe 30 /40 .
But every case is different, so you'll only know when you see the actual tests.
My experience of carbimazole for graves - I lost about 1/2 stone in the weeks prior to diagnosis and returned to my usual weight once treatment started. I perhaps put on a couple extra pounds as I went hypo for a short bit but dose was tweaked and they came off quickly. In short, I’m the same size as I’ve always been! Good luck!
Hi,I was diagnosed with graves and lost loads of weight unfortunately carbimiazole was not effective despite being prescribed a high dosage. Eventually I was advised to have radio active iodine treatment and now on levothyroxine and have put loads of weight as under active. Maybe different for everyone that’s my experience wish you all the best 🙂
You might like to dip into the Elaine Moore Graves Disease Foundation website :
Elaine had RAI, as did I back in 2005 and I've had to dig myself out of my unwellness post this treatment option which I deeply regret.
Yes I can understand and relate to why you feel like that I can honestly say I feel worse now being under active than being over active. However radio active iodine treatment was recommended for me as I was extremely overactive that the doctors thought I had had it all my days even though I was in my 30s when it was diagnosed. Thank you for the information I will defo have a read 😊 take care x
Hi, exactly the same happened to me. GP practice baffled by excessive weight loss, excessive sweating, rapid heart rate and feeling dreadful for weeks - also seemed to miss read thyroid test results and I was constantly being hooked up to ECG with these symptoms! Eventually I was sent to urgent treatment dept at local hospital and I was diagnosed with Graves within an hour of blood testing. I went through 18 months of ‘block and replace’ - mix of Carbimiazole and thyroxine ;which is dampening the thyroid down with the Carbimiazole and giving you back measured doses of thyroxine - along with beta blockers to control heart rate. This seems standard treatment for at least 18 months.
Didn’t work and I was still a mess 18 months on, shaking, sweating, with crazy/vivid nightmares from the medications.
Out of desperation I agreed to the RAI (iodine pill) which ‘nuked’ the thyroid. The hope being it’s not completely destroyed.
I still have Graves but due to the RAi I now have an under active thyroid and on doses of 100-125mg a day over 7 days a week (for the rest of my life). Ive since gained 3 stones - not uncommon when under active thyroid.
Since the original diagnoses I’ve never really been right -aching joints, lethargic, sluggish, brain fog and mega sweating persists. I’m presently trying Sage tabs to try and elevate the sweats - with a tiny bit of success.
Good luck Princey07 - read up all u can.
Thank you Gravety, it sounds like you’ve had a nightmare - I’m sorry.
Do you regret RAI? X
Hiya, I think I do really. I had a bad reaction to the RAI pill (my body flooded with thyroxine) and I was dreadfully ill - which was never properly explained could happen. The thyroid is an important gland and responsible for keeping organs and processes ticking over - should we be nuking it Willy Nilly?
I’m not entirely sure my current hypOactive thyroid state is any better than when I was pre-nuked and hypEractive - accept I now look like I’m constantly eating all of the pies!
The author and campaigner Elaine Moore, regrets having RAI. I so hope you can be stabilised without needing it.
A tip - if u smoke give it up - as higher percentage chance of Graves related eye disease if a smoker.
Hi. I lost weight at the very start before diagnosis. Since then and on Carbimazole I have had no weight problems. I can control my weight easily when I have put a little on due to having had too much good food and wine. I weigh the same now as before I developed Graves 8 years ago. I refuse to let Dr's dictate my treatment as they want to ablate my thyroid, I could not cope with putting weight on if I was hypo. Carbimazole works well for me combined with a bit of diet sense.
Good luck💜
I lost nearly 14 lbs just before my diagnosis of Graves, and was eating like a horse. It took a while to regain my weight by extra eating. Good luck.
Hello there, I have graves disease and have been on carbimazole since I was diagnosed in 2018.I started on the titration method of treatment which slowly reduces carbimazole to get the lowest dose to control the thyroid but that wasn't successful for me.I started on 40mg per day and went down to 20mg but it didn't work for me.I am now on a combination called block and replace where I take 40mg of carbimazole to block my thyroid and at the moment 75mcg levothyroxine to replace it each day.This has also been a bit up and down for me as I was on 100mcg levothyroxine and my t4 was good but it went too high and I ended up with weekly migraines and a fast heart rate. I have had to reduce it.As far as my weight is concerned when I was first diagnosed my t4 was in the 50's and I had lost about half a stone and my legs were like matchsticks. As my t4 came down the weight slowly came back on.I have had a bit of fluctuation of about half a stone on.For me I don't think it has anything to do with the carbimazole but my t4 levels.If they have been too low I feel sluggish and don't have the energy to do much.Hence sitting a lot, watching TV and unfortunately snacking.Sweets are a weakness.At the moment my t4 is just above top of range so I feel more energetic and am less likely to sit and snack.Therefore for me I don't think carbimazole has affected my weight but it is my t4 levels which have.Hope this helps.
Yes I have you’ll have to see what your body is intolerant of like for me was all the white stuff , rice bread potatoes and all I use my medicine at night or very early in the morning, then eat the other way round anything with high carbs in the early afternoon or morning and from 7pm strictly on intermittent fast then you’ll be able to control your weight , you’re young so you will be fine always notice when your body is hyper active especially metabolic will indicate and trace back what you are to trigger the symptoms I hope this helps I’ve been having very great results now and please rest as much as you can
Hey, I lost weight when my Graves’ was untreated. I’m back to my normal weight now that my thyroid hormone levels have been stabilised, and I’m still taking Carbimazole. I do try to eat a healthy, nutrient dense diet, and I exercise regularly (nothing too strenuous), so I don’t know if that has anything to do with it. Weight gain can happen with Carbimazole, but it’s not always the case. I wouldn’t stress too much about it at this stage though 💛
People who are hyperthyroid often find they lose a lot of weight very quickly initially, then put it all back on again as their thyroid levels come down, so don’t expect any weight loss as a result of being hyperthyroid to be permanent.
While you are very hyperthyroid, you are likely to eat more and in fact, you will be burning more calories. I also found I was permanently thirsty, so eating more sauces than usual. Initially you won’t put in weight as a result of this because your body will burn off the extra calories. The problem is, this phase doesn’t last very long, and it’s very easy to develop. habit of eating too much and too much of the wrong food.
If you are sufficiently hyperthyroid to need 40mg carbimazole/day, you do need to bring your thyroid levels down as otherwise you could develop serious health issues. I wouldn’t try to lose weight during this phase, but making a point of eating a healthy , balanced diet, and avoiding eating between meals will reduce the risk of putting on any more weight than the amount you may have lost when you first became ill.
Once my thyroid levels had stabilised and I was well enough to be bothered cooking ‘proper’ meals for myself and to take exercise, I found I could lose weight, even though I was still taking carbimazole.
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