Prozac is a medication commonly used to treat anxiety whereas risperidone is an antipsychotic that is used to treat irritability and behavior problems in individuals with autism-spectrum disorders. The best that I can tell you is that the medication may help. The most important thing is to make sure that you have a psychiatrist that you work well with and who is responsive to your needs. Treatment of these types of problems is often a long term process and, while this particular dose of Prozac may or may not work, the important thing is to have a psychiatrist that you are comfortable with working with you on developing a long-term solution for the issues your son is facing.
Thanks for your comments. I do have a psychiatrist that is very good she is trying to get a mental health assessment for my son in a residential setting., she prescribed the prozac for the time being due to the rapid deterioration in my son's mental health.