Which drug is typically used to treat hyperthyroidism?

Methimazole is a thioamide antithyroid medication that is commonly used to treat hyperthyroidism, particularly in conditions like Graves' disease. It works by inhibiting the enzyme thyroid peroxidase, which is essential in the synthesis of thyroid hormones. By blocking this enzyme, methimazole reduces the production of thyroxine (T4) and triiodothyronine (T3), helping to alleviate the symptoms of hyperthyroidism.

In contrast, levothyroxine is a synthetic form of the thyroid hormone thyroxine (T4) and is used to treat hypothyroidism, not hyperthyroidism. Propylthiouracil (PTU) is another medication that can also be used in hyperthyroidism treatment, but it is less frequently used than methimazole due to its side effect profile. Thyroid extract, on the other hand, contains active thyroid hormones and is not used for hyperthyroidism as it would exacerbate the condition. Therefore, methimazole is the most appropriate choice for managing hyperthyroid states.