Hi lovely lady this has just happened to me. I was on 10 my and now raised to 40mg. I did get few headaches for a week but this week seem to be fine. If you have been told u need to take 40 then obviously for reason. My doctor said side effects usually last no more than 2 weeks. U may have none. Good luck x
I would be concerned about the rashes and would see your doctor as soon as possible. I have had two serum sickness reactions, (severe allergic reactions) one of them 2 weeks after I finished an antibiotic, This last one manifested as a rash all over my body. This last reaction required a week of steroid medication (Prednisone) to stop it. Many doctors are not familiar with serum sickness and therefore do not diagnose or treat it properly so I would raise the question with your doctor and ask him/her if he/she thinks this is what you have. An Immunologist would know for sure if this is what you have and there are blood tests that can be done to diagnose it.
I wouldn't think you would need to be on more carbimazole than it takes to keep your resting pulse at 80 beats per minute, and I think that big of a jump in how much you take is very unusual.
I got itchy palms and feet at taking less than that of methimazole, not to mention typical hypothyroid symptoms.
If you are still having an elevated heart rate while on carbimazole, your doctor should add Propranolol to your treatment. Also, as I have posted to this Board before, adding Acetyl-L-Carnitine (amino acid from Health Food store) to your regimen will cause your thyroid values to normalize and you will then be able to decrease the Carbimazole. You will also feel better.
Thank you ladies for the replies. I started on the 40 mg and have been having bad heart palpitations! The doctors just did a heart trace (hours later when it had calmed down) and said there was no underlying heart problem and it was just my thyroid causing it. I'm going to mention the propranolol and see if they'll give me this to help. My resting heart rate is between 90-110. I'll also get to my local health food shop, thanks for the info