What Causes Frequent Attacks Of Epilepsy In A Child?

hi my son is 23months old and he had his first attact last year december and he was put on EPILIM LIQUID at a dose of 2.5ml twice a day. but on the 2nd of june he had the attct again and his doctor increased his dose to 5ml twice a day,and last night i gave him his dose but he had the attact at 01:40 he woke out of it and still had the attact at 05:50 well he slept well till 08:30 i feed him and gave him the dose then at 10:15 he got the attact again and we took him to hospital and he got the attact again at 12;05 then again at :25.what can be going so wrong.he even lost weight he was 12.5 and now he is at 11.4but he is eating well.