What is the primary treatment for hypothyroidism?

• A. Levothyroxine
• B. Methimazole
• C. Propylthiouracil
• D. Radioactive iodine

Answer: (A)

Replacing missing thyroid hormone to restore normal metabolic function is the main idea here. In hypothyroidism, the standard treatment is lifelong thyroid hormone replacement with levothyroxine, a synthetic form of thyroxine (T4) that the body converts to the active hormone as needed. The goal is to normalize thyroid-stimulating hormone (TSH) levels and free T4, with dose adjustments guided by regular monitoring and individual factors like age, weight, pregnancy status, and other health conditions. Antithyroid drugs such as methimazole and propylthiouracil reduce hormone production and are used for hyperthyroidism, not hypothyroidism. Radioactive iodine damages or destroys thyroid tissue and is also used for hyperthyroid conditions or cancer, not replacement therapy. Therefore, levothyroxine is the primary treatment.