I was put on keppra after 35 years of dilantin. I use 2-100mg at bedtime and have never had a problem on this dosage. Recently my Neurologist retired. My new neurologist prescribed 1000 mg a day of keppra. 500 mg am and 500 mg pm. He was weening me off dilantin so started with same dose plus prescribed dose of keppra and gradually down to the 500 mg twice a day of keppra. It has been a horrible experience. I got very weak within two days and developed a horrible cold and so tired I could not make it through a full day of work. I feel as though my whole immune system is being effected by the change. Why should I continue on keppra when I did excellent on dilantin? The new Dr s nurse told me to give it another week. I couldn t miss work and can t imagine why I d want to feel so horrible so I went off the keppra and back to my regular dose of dilantin. What do I do to get my prescription changed back?