Clozaril causes TD, so make sure he doesn't stay on that,either. It also carries one of the highest risks for seizure, 1-2%... Not really good for treatment of Autism, but rather treatment resistant schizophrenia.
Please do not stop Risperidone cold turkey.Please remain at the dose he is taking for next 2 weeks and see his Psychiatrist and she will taper it down or replace it with a medication called Clozaril if it is Tardive.Most likely it could be a temporary movement disorder called Akithisia which will go away once Risdone is stopped.Stopping Risperidone cold turkey can provoke an awful withdrawal syndrome or return of original symptoms so wait till you see his new doc.I went through similar problems when I stopped Risdone suddenly.My Psychiatrist restarted me on low dose risdone of 1 mg and is tapering me off in 4 weeks.my side effects have abated and I am 16 days away from stopping Risperidone.