What is the first-line treatment for hypothyroidism?

Levothyroxine is considered the first-line treatment for hypothyroidism due to its effective replacement of the deficient thyroid hormone, thyroxine (T4). Levothyroxine is a synthetic form of T4 that helps to restore normal levels of thyroid hormone in the body, which is crucial for regulating metabolism, energy levels, and overall physiological function.

The dosage typically starts between 50 to 100 mcg, depending on the patient's age, weight, and severity of the hypothyroidism. This tailored dosing enables clinicians to adjust levels appropriately to achieve optimal thyroid function while monitoring for any symptoms of over- or under-treatment.

Liothyronine, while it is another thyroid hormone (T3), is not the first line because most patients can effectively manage their condition with T4 replacement alone. Using T3 can sometimes complicate dosing and requires careful monitoring.

Propranolol is a beta-blocker that is primarily used for the management of symptoms associated with hyperthyroidism and does not treat hypothyroidism.

PTU (propylthiouracil) is an antithyroid medication used primarily in the treatment of hyperthyroidism and is not indicated for hypothyroidism.

Therefore, Levothyroxine not only directly