I agree with the others that the testing is a good idea given his fatigue and hazy feeling. It's rough to be a teenager and having the stress of starting college, let alone having the additional stressors like the Dilantin and epilepsy itself to deal with. If all the tests check out ok, does he have a primary care doctor that can check him over for anything else that may be causing problems (as suggested by ShakinMommy)? If he has a lot of stress with school right now, maybe the best thing in the world will be the end of the semester (!) Is there something going on in his life causing emotional stress that could account for his cognitive/ fatigue problems? Who can he talk to when something really bothers him?
It's got to be stressful for you too. Many people on this Forum can tell you about their experiences with declining cognitive, memory function as well as the endless battle with fatigue. If it is determined that it is indeed the epilepsy causing the cognitive problems, then, keeping a sharp mind and lowering the stress is the best thing he can do. It will also help you too to pamper yourself by reducing stress whereever YOU can!
Good Luck to you and your son, Hang in there... Glenda
complex partial seizures since 22
lamictal 200mg 2x/d
zonegran 150mg 3/d