Clozapine was the first of the new "atypical antipsychotic" medications. It has been shown to be more effective than older antipsychotics, but the possibility of severe side effects – in particular, a condition called agranulocytosis (loss of the white blood cells that fight infection) – requires that patients be monitored with blood tests every one or two weeks. For this reason newer atypical medications are often prescribed first.
Clozapine: Efficacy and Safety
Clozapine information from mentalhealth.com
