Loxapine versus perphenazine in psychotic patients. A double-blind, randomized, multicentre trial.

A double-blind, randomized, multicentre trial was carried out in 47 psychotic patients to evaluate the efficacy of oral treatment with loxapine compared with perphenazine. In total, 22 patients were included in diagnostic Group I (cases of acute schizophrenia and psychogenic (reactive) psychoses). The average maximum daily dose was 60.0 mg in the loxapine group and 36.8 mg in the perphenazine group. After 3-weeks' treatment, no significant differences were found between the two treatment groups according to the Brief Psychiatric Rating Scale (BPRS), Clinical Global Impression (CGI) Scale or side-effect records. Twenty-five patients were included in diagnostic Group II (cases of chronic schizophrenia). The average daily dosage was 81.1 mg in the loxapine group and 90.1 mg in the perphenazine group. After 10 to 12-weeks' treatment, no significant differences between the two treatment groups could be found according to BPRS, CGI scale, Nurses' Observation Scale for In-patient Evaluation (NOSIE) or side-effect records. The diastolic blood pressure (lying and standing) tended to increase slightly in both treatment groups. In conclusion, it was found that loxapine and perphenazine seemed to be equally effective and, based on experience with parenteral loxapine treatment, it is suggested that further investigation of oral loxapine should be carried out in psychotic patients in whom agitation is a feature.