Which medication is used to treat hyperthyroidism by inhibiting the synthesis of thyroid hormones?

The medication that is used to treat hyperthyroidism by inhibiting the synthesis of thyroid hormones is Methimazole. This drug works by blocking the enzyme thyroperoxidase, which is crucial in the production of thyroid hormones (T3 and T4). By inhibiting this enzyme, Methimazole effectively reduces the levels of these hormones, helping to manage conditions such as Graves' disease or other forms of hyperthyroidism.

Levothyroxine, often associated with hypothyroidism treatment, actually serves to replace or supplement deficient thyroid hormones rather than inhibit their production. Propranolol is a beta-blocker that can help manage symptoms of hyperthyroidism, such as tachycardia and anxiety, but it does not act on hormone synthesis. Synthroid, like Levothyroxine, is a form of thyroid hormone replacement and is therefore not appropriate for treating hyperthyroidism. Methimazole specifically targets the underlying issue of excessive hormone production, making it the correct choice for addressing hyperthyroidism.