Hello, Thanks for posting in HCM If the symptoms present as your described i.e fever then seizures and it started when he was 1.5 years old, then your son is suffering from recurrent febrile convulsions ( seizures due to fever) which could be caused by any of the numerous causes of high fever in children like Acute otitis media, respiratory infection, meningitis, malaria, sepsis, throat infection etc Careful examination and laboratory testing will need to be done in order to rule out any infectious causes of the febrile seizures so that it could be treated first. If EEG is abnormal now, it could be redone in a couple of weeks when the child is stable with no illness to see if still abnormal. Emphases on ruling out infections before concluding on epileptic seizures is very important as treatment for it is usually long term and might come with side effects. Now, for the side effects of valparin 200 syrup, you might expect to see - dyspepsia - weight gain - jaundice - nausea - vomitting - clay-colored stool - any other abnormally that is noticed after start of the medication You need to understand that if your doctor has made the decision to place your son on an antiseizure drug, then he/she has weighed the benefits it has over the risk involved taking it. But be rest assured that side effects could be minimal and of no severity as compared to its benefit. But if of the above effects show up, just contact your doctor. Hope this helps