Objective: To ascertain whether the therapoutic effect of 131I is affected by the additional use of thyrostatic medication.
Methods: One hundred and eighty-seven patients with Graves' disease (GD) were randomly assigned to treatment with 131I alone or plus thyrostatic medication(PTU) 3 days after the beginning of 131I therapy. All patients were examined every month for six months after treatment.
Results: The cure of hyperthyroidism occurred in 71 of 93 patients(76.3%) treated with 131I alone and in 76 of 94 patients(80.5%) treated with 131I plus thyrostatic medication(PTU). There were no significant differences in cure rate between the two groups.
Conclusion: The additional use of thyrostatic medication 3 days after the beginning of 131I therapy will not affect the efficacy of 131I in the treatment of GD.