Iodine 131 treatment for hyperthyroidism is usually effective in about 1 month, and thyroid function returns to normal in about 60% of patients after 3 to 4 months of treatment. The exact time is related to the patient’s personal situation. Hyperthyroidism can be treated with Iodine 131. This is a precise treatment, which not only has a high cure rate, but also has a low recurrence rate. However, Iodine 131 takes time to work, and it takes about 1 month to show its effect. For patients whose hyperthyroidism has not resolved after 3 to 6 months of iodine 131 treatment, another iodine 131 treatment may be recommended. However, it should be noted that iodine 131 treatment may cause some adverse reactions, such as nausea, vomiting, dizziness, etc. Patients should pay attention to the observation of their own condition during the treatment and pay attention to their diet to avoid aggravating the condition. If discomfort occurs, it is recommended to consult a doctor promptly.