Risperidone for children. Any experience

My son's psychiatrist has just prescribed this for my 13 year old son. He has very high anxiety and a ASD and ADHD diagnosis. Although not violent he is struggling to access school and is becoming more isolated at home. He also really struggles with sleep. Has anyone used this for their child? I am just keen to hear other people's experiences as I am very worried about using medication.  Many thanks.