Diagnosis and treatment of Graves disease

To review the etiology, diagnosis, and clinical presentation of Graves disease and provide an overview of the standard and adjunctive treatments. Specifically, antithyroid drugs, beta-blockers, inorganic iodide, lithium, and radioactive iodine are discussed, focusing on current controversies.

Primary articles were identified through a MEDLINE search (1966-July 2000). Key word searches included beta-blockers, Graves disease, inorganic iodide, lithium, methimazole, and propylthiouracil. Additional articles from these sources and endocrinology textbooks were also identified. We agreed to include articles that would highlight the most relevant points, as well as current areas of controversy.

Graves disease is the most common cause of hyperthyroidism. The 3 main treatment options for patients with Graves hyperthyroidism include antithyroid drugs, radioactive iodine, and surgery. Although the antithyroid drugs propylthiouracil (PTU) and methimazole (MMI) have similar efficacy, there are situations when 1 agent is preferred. MMI has a longer half-life than PTU, allowing once-daily dosing that can improve patient adherence to treatment. PTU has historically been the drug of choice for treating pregnant and breast-feeding women because of its limited transfer into the placenta and breast milk. Adjuvant therapies for Graves disease include beta-blockers, inorganic iodide, and lithium. beta-Blockers are used to decrease the symptoms of hyperthyroidism. Inorganic iodide is primarily used to prepare patients for thyroid surgery because of its ability to decrease the vascularity of the thyroid gland. Lithium, which acts in a manner similar to iodine, is not routinely used due to its transient effect and the risk of potentially serious adverse effects. In the US, radioiodine therapy has become the preferred treatment for adults with Graves disease. It is easy to administer, safe, effective, and more affordable than long-term treatment with antithyroid drugs. Hypothyroidism is an inevitable consequence of radioiodine therapy. Radioiodine is contraindicated in pregnant women because it can damage the fetal thyroid gland, resulting in fetal hypothyroidism. Bilateral subtotal thyroidectomy, which was once the only treatment available, is now performed only in special circumstances. In addition to the normal risks associated with surgery, laryngeal nerve damage, hypoparathyroidism, and hypothyroidism can occur following that procedure.

Despite extensive experience with medical management, controversy prevails regarding choosing among the various drugs for treatment of Graves disease. None of the treatment options, including antithyroid drugs, radioiodine, and surgery, is ideal. Each has risks and benefits, and selection should be tailored to the individual patient.