Does your metabolism go back to normal after you stop taking carbimazole?

[James101]

I read that carbimazole slows down your metabolism, thus the potential to gain weight rapidly if you’re not extremely careful. But does the metabolism return to normal when withdrawn from the medication? I’m so done with this weight gain, it’s the worst side effect I’ve had, and I’ve had a lot. My metabolism is super fast, so when I do withdraw, I expect my weight to drop down, not without effort, but fortunely, not with as much effort as some people would.

I was diagnosed as Hyper with Graves last June. I’ve geenerally always been very skinny and It wasn’t for a lack of eating. I could eat just about anything and it wouldn’t effect my weight. I remember, as a 14 year old (I’m 20 now), it took me eating a McDonalds meal genuinely around 8 times a week to put on weight.

When I was diagnosed, I was taking 9 carbimazole tablets a day. I was on that dosage for about 3-4 months. Now I’m on only 2 a day.

I had maintained a weight of early 80kg, lightest probably being 74-75kg until I began to take carbimazole last year. Now I weight 94kg. As I said, I have a very tall & skinny frame, so this rapid weight gain doesn’t flatter me. Just imagine a 6’5 guy, with a skinny frame, but weighs 94kg/207 pounds. My face is so unnaturally puffy, and my stomach is so big.

Since my rapid weight gain, I took on a healthier approach, more healthy eating than calorie cuts. It wasn’t 100%, it was mostly just not overdoing my calorie intake and significantly reducing junk food, fast food & sugary drinks. It’s the first time in my life I’ve ever been eating healthy. Plus I started weight training, and began core & cardio exercise. I think I’ve lost at least 1 kilo but there’s a difference when I weigh myself vs when I’m weighed at my specialist doctor, as I’ve fully clothed there.

[greygoose]

I don't think it's that carbi reduces metabolism directly, but it reduces the production of thyroid hormones. And, if you take too much, the T hormones reduce too far, and low T3 causes low metabolism. Stop the carbi, and the production of T hormones should increase, and the metabolism should return to normal. But, it's a difficult balance to achieve.

[Qwerty12345]

I think everyone has a different experience. I had lost around half stonewhen I was diagnosed with graves. Once treatment started I put that weight back on but none extra. I’m not on treatment now and weigh the same as I did pre-graves.

[Valarian]

When you were 14, a lot of your energy would have been going into growing. Your body put a lot of effort into growing you to be 6'5 ! Thyroid hormones regulate how your body uses energy (ie your metabolism), and when you are hyperthyroid, your metabolism will typically be faster than usual. As Greygoose says, the main impact of Carbi on weight is indirect, in that by bringing thyroid levels within range, your metabolism should come back to its normal rate, so you will use less energy than when you were hyperthyroid.

I lost a lot of weight very quickly when I first had Graves', and due to my hyper metabolism became very hungry. For some months, I could eat whatever I wanted without putting on weight. In spite of knowing better, I didn't adjust my food intake as soon as I should have done as my thyroid levels, and therefore my metabolism came down, and have put most of the weight back on. The tiredness and muscle weakness associated with Graves' hasn't helped, as my exercise levels are still lower than they used to be ( something which I plan to correct now that the weather is better !)

Your endo will only be interested in weight change since your last appointment with them, so they will be going by their own records, which may record weight fully-clothed and with shoes on. The relative weight change between endo appointments should be roughly the same, although the actual weights recorded fully-clothed at the endo's will obviously be higher than those you take yourself.

If you are weight-training and eating a healthy diet, you may put on a bit of weight anyway, as muscle weighs more than fat. Your gym may have the sort of scale that can estimate body composition. I'm not sure how accurate these are, but relative difference over a few months may be interesting. One of the trainers should be able to advise.

Assuming you are able to achieve remission from the Graves', your thyroid levels should return to normal, along with your metabolism and energy levels. In the UK, for the best chance of achieving remission, it's usually recommended that you stay on Carbimazole for 12-18 months before taking you off altogether.

Keep up that healthy diet !