The use of antithyroid drugs.

The preoperative use of antithyroid drugs is mandatory if surgical treatment of complicated hyperthyroidism is contemplated. Six months to a year may be required for suitable preparation. The long-term use of antithyroid drugs is less effective for the "cure" of hyperthyroidism than is operation or the use of radioactive iodine. Propyl and methyl thiouracil are the antithyroid drugs of choice. Either of these thiouracil derivatives is capable of producing leukopenia. The antithyroid drugs exert no favorable effect on exophthalmos. The antithyroid drugs are suitable for the control of hyperthyroidism during pregnancy. The patient probably should not be kept hypothyroid during pregnancy but rather in a state of mild hyperthyroidism.