did they give you the cause of the hyperthyroidism -- ie
Graves (most likely) or a toxic nodule?
In the USA there is a tendency to use more I-131, but in many other countries (and in our office) we often use anti-thyroid meds such as methimazole for Graves and consider surgery for treatment as well. If it is a hot nodule, then would recommend either I-131 or surgery (w/ an expert thyroid surgeon).