Rule is:
Whenever we donot see improvement in any field in life, it just means efforts in that direction are not enough or even if you are making lots of efforts, the time given for the directed efforts is not enough !
Risperidone is one of the approved drugs for behavioural issues in autism. It is not for speech development. its job is to keep the mind and body steady to facilitate learning receptiveness. Developing or focussing speech without focussed listening / understanding/ thinking is like empty vessel making sound.