The effects of the availability of risperidone and olanzapine on the indica
tions for which clozapine is prescribed (treatment-resistance, treatment-in
tolerance, and/or negative symptoms) were examined for 252 patients with sc
hizophrenia who began treatment at our hospital between June 1990 and June
1997.
There were no statistical differences in the indications for clozapine trea
tment before and after the availability of either risperidone or olanzapine
. Furthermore, there were no significant differences in the frequencies of
the indications in subgroups of patients who had previously received a tria
l with risperidone or olanzapine, as compared with the remaining patients.
The indications for clozapine appear to have been unaffected by the advent
of risperidone and olanzapine; however, we noted a decrease in the absolute
number of patients starting clozapine after risperidone became available,
More recently, the majority of patients referred for treatment with clozapi
ne had received previous trials with risperidone or olanzapine.