Thyroid UK
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hi,i was diagnosed with a toxic nodular goiter one year ago. i had a terrible feeling of anxity. i felt better after taking carbimazole 20mg for 4 months and my tsh,t3,t4 were all normal after one month of treatment so i reduced carbimazole dose to 15mg but i started to feel bad again after 2 months then i returned to 20mg dose. now i am feeling ok. my question is when do i reduce carbimazole dose again and is it ok to take radio active iodine for toxic nodular goiter?

3 Replies

Welcome to the forum, Elsaba.

You should be having monthly blood tests to check your thyroid hormone levels while you are on Carbimazole. When TSH is rising and FT4 and FT3 levels falling that is when dose should be reduced.

Radioactive Iodine ablatement (RAI) will destroy your thyroid gland and nodule which will stop you being hyperthyroid but is very likely to make you hypothyroid within a few months. If your goiter is small the RAI may shrink it but large goiters often need surgical removal ie thyroidectomy rather than RAI.


i do not understand why my doctor does not recommend (RAI) for (TNG).

is it used for non toxic goiter only or is it the risk of cancer after a long time?


Elsaba, It can take 6-18 months for Carbimazole to regulate hyperthyroidism. After that it is often possible for remission but if you have Graves antibodies the remission isn't likely to be permanent and RAI may then be offered. Most people will advise that destroying your thyroid gland should be a last option and there is a slightly increased risk of developing Leukaemia after RAI.

Higher dose RAI is given to thyroid cancer patients after thyroidectomy to kill off remnant thyroid cells in the body to prevent recurrence of thyCa.


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