Thyroid UK
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Being hyper which is a better therapy, antithyroid drugs on their own or block & replace?

I'm seeing my endo Monday and just wondered what people's views are on here as I might bring it up with him. I'd never even heard of block and replace until visiting this forum, despite having Graves for around 6 years and now on my second course of PTU after a relapse. Just curious as to why it's never been offered to me as I still feel awful despite being in "normal range".

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This is advice from Dr Toft, ex President of the BTA:-

5 Patients with hyperthyroidism often ask for advice on drug treatment versus radioiodine therapy. Can you summarise the pros and cons of each?

The three treatments for hyperthyroidism of Graves’ disease – antithyroid drugs, iodine-131 and surgery – are effective but none is perfect.4

Iodine-131 will almost certainly cause hypothyroidism, usually within the first year of treatment, as will surgery, given the move towards total rather than subtotal thyroidectomy.

There is no consensus among endocrinologists about the correct dose of thyroid hormone replacement so patients may prefer to opt for long-term treatment with carbimazole. Standard practice is that carbimazole is given for 18 months in those destined to have just one episode of hyperthyroidism lasting a few months.

But there’s no reason why carbimazole shouldn’t be used for many years in those who do relapse. Any adverse effects such as urticarial rash or agranulocytosis will have occurred within a few weeks of starting the first course.

Iodine-131 treatment for toxic multinodular goitre is the most appropriate choice as hypothyroidism is uncommon. Surgery would be reserved for those with very large goitres and mediastinal compression.

Once hyperthyroidism has developed in a patient with a multinodular goitre, it will not remit and any antithyroid therapy would have to be lifelong.


Maybe that's not the treatment preferred by your hospital. It's what my place uses but I have a feeling they don't offer their patients titration. Not sure one is better than the other, they are just different. B&R might be easier for the hospital, wipe out the thyroid then give it artificially increasing as the patient needs it or you give an ever reducing amount of Carbimazole or PTU like you had.

As for ranges - well what is normal for you might not be normal for me and the range is so enormous it couldn't possibly suit everyone. Try telling your doctor 'Yes, I know my blood results are normal but 'the range' is so wide it would be difficult for them not to be and as I still feel ill they are obviously not optimal for me'

I think that might be one of the advantages of B&R - the way it went - ie I was given enlugh Carbimazole to stop me producing any T4 I could see the test results when I felt good and so I knew how much levo I needed to feel good, but maybe you can tell that from how you were treated, I don't know, good luck anyway.


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