RELATION OF PLASMA FLUPHENAZINE LEVELS TO TREATMENT RESPONSE AND EXTRAPYRAMIDAL SIDE-EFFECTS IN FIRST-EPISODE SCHIZOPHRENIC-PATIENTS

Objective: The aim of this study was to determine the relation between plasma fluphenazine levels and clinical response in first-episode sch izophrenic patients. Method: Data from 36 first-episode schizophrenic or schizoaffective inpatients diagnosed according to the Research Diag nostic Criteria were evaluated. The patients received open, standardiz ed treatment with fluphenazine, 20 mg/day, for at least 4 weeks. Psych opathology was assessed biweekly, and plasma fluphenazine levels were ascertained weekly. Patients were classified as responders or nonrespo nders, and correlations between their neuroleptic levels and ratings o f psychopathologic and extrapyramidal symptoms were computed. Results: Plasma fluphenazine levels for weeks 1 through 4 were significantly c orrelated with each other but were not correlated with age, gender, di agnosis, or race. Mean neuroleptic levels (weeks 3 and 4) were not dif ferent between responders and nonresponders and were not correlated wi th measures of psychopathology or extrapyramidal symptoms. Conclusions : These results do not indicate an association between plasma fluphena zine levels and response to treatment or extrapyramidal side effects i n first-episode schizophrenia. The disparity between the results of th is study and those of previous studies may be due to methodological di fferences or to a biologically based difference between first-episode and chronic patients.