A 30-year-old woman complains of palpitations, fatigue, heat intolerance, and insomnia. She is otherwise healthy. She and her husband desire children and are not interested in contraception. On physical examination, her extremities are warm and she is tachycardic. There is diffuse thyroid enlargement and proptosis, as well as thickening of the skin in the pretibial area. Laboratory testing reveals a free T4 value of 3.2 ng/dL (normal 0.9-2.4) with an undetectably low TSH level. Radioiodine uptake at 24 hours is 42% (normal 10%-30%). What is the best treatment plan for this patient?
A. PropylthiouracilAntithyroid drugs are the treatment of choice in a patient with Graves disease who may become pregnant. Iodine 131 has been used successfully in Graves disease and is a reasonable option if the patient is willing to practice secure contraception for at least 6 months. However, it often causes permanent hypothyroidism and may worsen ophthalmopathy in some patients. The treatment of choice is the oral agent propylthiouracil. Propylthiouracil is chosen in cases such as this owing to low transplacental transfer. Methimazole is preferred in men and non–childbearing women because it can be given once daily. Propranolol relieves the adrenergic symptoms resulting from Graves disease but will not treat the underlying disease. Subtotal thyroidectomy is reserved for thyrotoxic pregnant women who have had severe side effects to medication. Surgical complications include hypoparathyroidism and recurrent laryngeal nerve injury. Corticosteroids are used in thyroid storm but not in the stable patient with Graves disease.