Hello! Welcome on Healthcaremagic! I read carefully your question and understand your concern. As a neurologist, I would not prefer long term treatment with Dylantin, because of its possible adverse effects, especially in young patients. For this reason, I would recommend consulting with his attending physician and discussing the possibility of switching to carbamazepine or valproate, which are better tolerated. But, the switching should be done very gradually and under strict medical supervision. You should discuss with his doctor on these treatment options. Hope you will find this answer helpful! Best wishes, Dr. Aida