seizures
"My 14 yr old son has been on Vimpat coupled with Keppra and although it is not recommended for children, it has given me peace of mind.  He has been seizure free for over two years.  Side effects appear to be minimal, he does have short term memory loss, like walking into the kitchen and forgetting why he came in there.  He especially forgets chores, but I don't know if it's because of the medicine or because he is just a typical lazy teenager."