seizures
"Although this medication did decrease my daughters absence seizures, if she took this at any time 30 min before or after eating, she had a severe reaction.  Her throat would burn inside and out, her face would flush, she would get dizzy and unable to focus. This would last about 5-10 min. and then she would get so tired, she would instantly fall asleep and sleep for hours.  She was at a pretty high dose during this time 1050mg 2x daily.  We finally stopped this medication, because of the stress of having to watch so closely when she ate and when she could take this medication."