Plasma prolactin and fluphenazine concentrations in patients receiving fluphenazine decanoate: stability over injection intervals.

Plasma prolactin and fluphenazine concentrations were measured in a group of 17 patients (9 males, 8 females) with schizophrenia who were receiving chronic treatment with fluphenazine decanoate. Neither measure was significantly correlated with clinical effect, as measured by the Brief Psychiatric Rating Scale, at any of the 5 pre-injection times examined. None of the measures showed statistically significant (P greater than 0.05; MANOVA) variations with time. Neither measure showed a significant correlation with the dose (expressed as mg/kg) of fluphenazine. The implications of the study for monitoring chronic treatment of schizophrenia are discussed.