To the Editor.— In a study of outpatient treatment of schizophrenia,1Kane et al reported that patients who received one tenth of the "standard dose" of fluphenazine decanoate had relapses more frequently than those patients who received the standard dose. They concluded that "The present results are somewhat discouraging for the low-dose range we chose to study." As a private practitioner treating patients individually, it surprised me that the results reported by Kane et al were so good when the patients were treated with standard doses of any magnitude. When patients are observed closely, one finds not only that different patients require different and unpredictable doses, but that the same patient requires different doses at different times to maintain a state of optimal well-being. True, a patient might not have a relapse into gross psychosis if he is given a dose that deviates by a factor of approximately two

In an attempt to begin to establish minimum effective dosage requirements for the maintenance treatment of schizophrenia, we undertook a double-blind comparison of low-dose fluphenazine decanoate (1.25 to 5.0 mg/2 wk) with the standard-dose regimen (12.5 to 50.0 mg/2 wk) in outpatient schizophrenics. For the first 126 patients studied, cumulative relapse rates at one year for the low dose were 56% and for the standard dose 7%, a significant difference. Despite the fact that very little dyskinetic symptomatology developed in the sample as a whole, the low-dose treatment appeared to have a significant advantage in producing fewer early signs of tardive dyskinesia. Severity of relapse and total cumulative dosage were also considered.