Hi My Son Has Praxis And Sensory Intergration Disorder He

Hi my son has praxis and sensory intergration disorder he is 6yr old he was prescribed Risperdal 0.5ml twice a day and serdep 50mg half a tablet .Just to add he been on respirdal for a while now it was just increased frp,0.4ml to 0.5 ml on the 1st april 2016 now since increase he is more impulsive at school I am not saying it the meds just wondering if it could be he is in a remdial school with a lot of impulsive kids.But he not been aggressive for a long time and is now a little more quick to react my question is can serdep as it is the new one cause this or could it be combination of the two just checking