Suggest Treatment For Nosebleeds Followed By Seizures And Tingling Body

My husband is 27, since about the age of 24 he has had seizures. We are not quite sure what the reason for the onset was and we are trying to figure that out. He has not had any traumatic accidents and seizures are not prevalent in his family. He used to get really horrible nose bleed before he had the seizures, then he used to get this tingling sensation all over his body, he said it felt like his entire body was relaxing and it felt comfortable. After about 6 months he started to get "seizures" where his entire body would go tense, he feels like he can't breathe, his face turns red, and he secures him self by holding tightly to whatever he is sitting on. He is resposive but he can't really talk. His neurologist prescribed him Depakote about a year ago and that stopped the seizures during the day but he still had them at night while he was sleeping. Now the Depakote is starting to become ineffective and he is having seizures during the day again and he says they are becoming increasingly worse and extremely painful. He goes to see the neurologist again but they just seem to be treating the symptoms and are ignoring the search for the cause. Do you have any suggestions?