Prolactin plasma levels after neuroleptic challenge predict clinical response in schizophrenic patients

J. Libiger, P. Czobor, V. Jirkalová, E. Malířová, I. Tůma

Research output: Contribution to journalArticle


Till now, the ability of prolactin (PRL) levels to predict treatment response during neuroleptic therapy has been explored with inconclusive results. Studies exploring PRL response in a test dose design are very scarce. PRL response to a chlorpromazine test dose failed to predict the outcome in a study by Meltzer et al. - We have investigated prolactin levels after a single oral dose of isofloxytepin or haloperidol in 29 schizophrenic patients, who were subsequently treated by the same neuroleptic. - In multiple regression analysis the set of 5 variables (baseline PRL level and PRL levels 2 and 6 hours after the test dose, drug group and sex) was significantly related to improvement (R2 = 0.69; F = 6.76; p = 0.0003). Only baseline PRL and drug group did not contribute significantly, a significant interaction of drug group and PRL levels suggests a different relationship between improvement and prolactin elevation in each treatment group. Partial coefficients of determination for PRL levels 2 and 6 hours after the challenge dose and for PRL/treatment group interactions were all about 30%. Patients improved after isofloxythepin had higher PRL levels (52.5 ng/ml) than non-improvers (16.5 ng/ml) after 6 hours. Methodological constraints of the study and reasons for differences in relationships of prolactin and improvement in various patient groups are discussed.

Original languageEnglish
Pages (from-to)106-114
Number of pages9
JournalHomeostasis in Health and Disease
Issue number3
Publication statusPublished - Jul 30 1996



  • haloperidol
  • isofloxytepin
  • prediction
  • prolactin
  • schizophrenia
  • test dose
  • treatment response

ASJC Scopus subject areas

  • Neuroscience(all)
  • Psychiatry and Mental health

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