Does Perphenazine Help In Treating Negative Thinking?

Yes, Please help me. My husband of nearly a year is schizoaffective and has been hospitalized over 30 times. He is now 50. I know that at some point a few months ago, he has his dosage reduces then after his mother passed away, he stopped taking his medication regularly. He showed symptoms of delusions and could or could not be keeping them from me. He does not share those at this point as he is suspicious and angry with me. He does however display all the attributes of negative symptoms. It is like speaking with an unpleasant stranger. His only medication is Perphenazine. Does this help effectively with negative symptoms? What can I do to help? How long do relapses last if they work themselves out?

Thank you,
Cherise