I started on Dilantin and lamotrigine for seizures but switched to Keppra because it was a “newer” medication. I had a horrible result. I was extremely irritable and had a reduced ability to control my emotions. I went back to my 2 previous drugs. My neurologist said different medications work differently in controlling seizures for different individuals. Work with your neurologist in coming up with with a “cocktail” of meds that control your seizures with the least side effects.