Previous work with chronic schizophrenic patients and a pilot study with nonchronic treatment-refractory schizophrenic patients indicated that very high doses of fluphenazine hydrochloride (1,200 mg/day) have a greater antipsychotic effect than do standard doses. Increased side-effects were not reported. In a double-blind six-week random assignment study, 18 nonchronic treatment-refractory patients received the very high dose and 13 the standard dose. The standard-dose treated patients had greater improvement on a variety of measures. Analysis of Inpatient Multidimensional Psychiatric Scale scores indicate that some patients taking very high doses had akinesia, and extrapyramidal side-effect that in part accounted for their inferior response.