PROLACTIN RESPONSE TO D-FENFLURAMINE CHALLENGE TEST AS A PREDICTOR OFTREATMENT RESPONSE TO HALOPERIDOL IN ACUTE SCHIZOPHRENIA

D-fenfluramine has been identified as a highly selective serotonin (5- HT:) releaser and re-uptake inhibitor. The objective of our study was to investigate prolactin response to D-fenfluramine challenge in non-m edicated, first episode schizophrenics. We hypothesized that 5-HT reac tivity call predict a response to the neuroleptic treatment. Twenty-th ree inpatients, 11 males and 12 females, at the Prague Psychiatric Cen ter participated in the study. Inclusion criteria were: ICD-10 diagnos is of schizophrenia, first episode or duration of illness shorter than 36 months. D-fenfluramine challenge test was performed before 4 weeks of the :haloperidol treatment. During the test, prolactin plasma leve ls were measured. The Brief Psychiatric Rating Scale (BPRS) was admini stered before and after the treatment. A statistically significant neg ative correlation was found between prolactin response to the D-fenflu ramine challenge and improvement of psychopathology measured by the ch ange in total BPRS score (p = 0.0004), in positive (p = 0.0403), negat ive (p = 0.0267), and anxiety-depression symptoms of BPRS (p = 0.0014) . Our data support the original hypothesis that there is a relationshi p between 5-HT system activity and treatment response. The higher resp onsiveness of the 5-HT system in first episode. non-medicated schizoph renics, was associated with a poorer treatment response to haloperidol , an antidopaminergic neuroleptic. (C) 1998 Elsevier Science B.V.