Graves' disease is an autoimmune disease and is the main cause of hyperthyroidism. This study aims to characterize the evolution of treatment with antithyroid drugs in patients with Graves' disease in a tertiary care referral center. We observed that the use of propylthiouracil was a predictor factor of a greater chance of having some adverse effect in relation to the use of methimazole. Regarding the evolution of treatment, high concentrations of TRAb were the main determinant for non-remission of the disease with the use of thionamides.