Augmentation with typical antipsychotics for patients who partially respond to antipsychotics

The serotonin-dopamine antagonists are effective antipsychotic drugs for a large number of patients suffering from schizophrenia. They are used routinely in Israel with patients who are resistant to typical antipsychotic drugs, although only clozapine is considered to be effective in those patients. Unfortunately, only some of those patients benefit from the use of the relatively new drugs. This leaves many patients resistant to treatment. The serotonin dopamine antagonists have a low affinity for D2 receptors in comparison with the classic antipsychotics. Their antipsychotic action involves other receptors, mostly 5-HT2. Method: We administered D2 antagonists as an augmentation to patients who are partially resistant to treatment with atypical drugs. Ten patients who responded partially to either clozapine or olanzapine were administered open-labeled with haloperidol up to 10 mg/day, or sulpiride up to 600 mg/day, or zuclopenthixol up to 30 mg/day for at least six weeks. Results: One of 4 patients who received olanzapine and sulpiride improved (CGI-5 to CGI-3). The only patient who received a combination of clozapine and haloperidol improved (CGI-4 to CGI-3). One of 2 patients who received a combination of olanzapine and zuclopenthixol improved (CGI-4 to CGI-3). Two patients who received a combination of olanzapine and haloperidol did not improve as did one patient who received a combination of clozapine and sulpiride. Conclusions: The results give some hope to chronic psychotic patients since three out of ten patients significantly improved in this preliminary trial. We believe that well controlled doubleblind studies are needed to evaluate the clinical significance of such combination regimens.