Keppra had a huge effect on my mood/temper and made me very drowsy. I went from 250 mg of Depakote twice daily to 750 mg of Keppra twice daily. I did not believe I needed such a high dosage, but my neurologist did not want to cut it. So, I did it own my own. I am now taking half a pill (half of 750) twice a day and have been so much better with my moods and drowsiness.