You have hyperthyroidism. The teratment options are medications (already taking), surgery and radioiodine treatment. Radioiodine treatment is one of the best options as it cures the disease within few months. The only long term side effect is induction of hypothyroidism which is very easy to treat by taking thyroid hormone replacement. In the current era indications of surgery are very few such as very large goiter, extension in the thorax (chest) and severe eye disease (ophthalmopathy).
You may continue to take medications for long time but problem is there are frequent fluctuations in thyroid functions, need for frequent tests and visit to doctor and if not controlled then long standing hyperthyroidism can lead on to osteoporosis and heart problem.