To observe the clinical value of 131 I in the treatment of hyperthyroidism. The weight of the thyroid was evaluated by palpation

131 I was taken orally by one dose method. The dose was calculated by actual absorption of 131 I/per gram of thyroid. 3—6 months after drug administration

the symptom

clinical manifestation and the serum hormone of the pituitary-hypothyroid axis were observed. In 105 cases

80(76.2%) were nearly recovered

among them 16(15.2%) had hypothyroidism in the early period. The allover recovering rate was 91.4% in one dose

but 9(8.6%) were recurred and can be controlled at a second dose. Therefore 131 I for the hyperthyroidism had a high recovering rate

low recurring rate and was very convenient. If the dose at an optimal range was controlled. The occurrence of hypothyroidism can be reduced to the acceptable level.