Levothyroxine sodium is a synthetic version of the thyroid hormone thyroxine (T4). It's prescribed primarily for hypothyroidism, where the thyroid gland doesn't produce enough hormone. This medication helps to restore normal thyroid hormone levels in the body. It's taken orally in tablet form once daily, typically in the morning on an empty stomach for optimal absorption. Dosage is adjusted based on individual health needs and thyroid hormone levels, with careful monitoring to avoid side effects such as hair loss, weight changes, or mood swings. Correct dosage is crucial for effectiveness, as too little can lead to ongoing symptoms of hypothyroidism, while too much can cause symptoms of hyperthyroidism. Regular check-ups with healthcare providers are necessary to ensure the medication is working effectively and thyroid function remains stable.