Carbimazole (Neomercazole) and Methimazole are common medicines used to treat hyperthyroidism. They reduce hormone production in the thyroid gland for people with hyperthyroidism; this will control the symptoms. However, some people taking these medicines may develop itching, rashes, arthralgia, liver toxicity, or low white blood cell counts (agranulocytosis). Although rare, these complications can sometimes be fatal.
People with Graves’ disease (an autoimmune form of hyperthyroidism) usually take Carbimazole for 18-24 months, following which it is stopped. People who continue to have hyperthyroidism are usually offered radioactive iodine ablation or thyroid surgery. However, there is scientific evidence that we can continue these drugs for a longer duration. However, people who decide to consume these medicines should check their thyroid functions as recommended by the doctor and also visit the doctor to check for any complications.
People with a condition called toxic nodular goitre (multinodular or single nodule) are also given Carbimazole for treatment. However, since these medicines don’t offer a cure, a decision for permanent treatment like radioactive iodine ablation or thyroid surgery is advised early. However, people at high risk for surgery or those who wish to be on medicines can continue to use it under supervision. So, extended periods of antithyroid drugs can be used under medical supervision for patients with hyperthyroidism. This treatment option can be discussed with your endocrinologist.
Dr.Mathew John,MD,DM