Pharmacodynamics and pharmacokinetics of haloperidol and reduced haloperidol in schizophrenic patients

Chang Wen-Ho, Lin Shih-Ku, Michael W. Jann, Y. W.Francis Lam, Chen Teng-Yi, Chen Chao-Tsao, Hu Wei-Herng, Yeh Eng-Kung

Research output: Contribution to journalArticle

38 Scopus citations

Abstract

Twelve male chronic schizophrenic inpatients, neuroleptic-free for at least 4 weeks, were given an oral test dose of 10 mg haloperidol (HAL) and reduced HAL (RHAL) in a random order, with a 2-week interval. Two weeks after the last test dose, the patients were given HAL, 5 mg orally twice daily for 7 days. Blood samples were drawn at baseline and between 0.5 and 24 hr after the test doses, and during HAL treatment as well. Plasma drug concentrations and homovanillic acid (HVA) levels were measured with high-performance liquid chromatography using electrochemical detection. HAL, but not RHAL, produced increments in plasma HVA (pHVA) levels at 24 hr after a test dose. pHVA levels remained higher than baseline during HAL treatment. Detectable intercon-version between HAL and RHAL was observed in eight patients. The capacity of the reductive drug-metabolizing enzyme system, however, was greater than that of the oxidative processes. The plasma RHAL:HAL ratios on days 6 and 7 were higher than and positively correlated with those at Tmax after a single dose of HAL and were negatively correlated with the HAL:RHAL ratios at Tmax after a single dose of RHAL. Thus, both reductive and oxidative drug-metabolizing systems probably contribute to individual differences in plasma RHAL:HAL ratios in HAL-treated schizophrenic patients.

Original languageEnglish (US)
Pages (from-to)239-249
Number of pages11
JournalBiological Psychiatry
Volume26
Issue number3
DOIs
StatePublished - Jul 1989

ASJC Scopus subject areas

  • Biological Psychiatry

Fingerprint Dive into the research topics of 'Pharmacodynamics and pharmacokinetics of haloperidol and reduced haloperidol in schizophrenic patients'. Together they form a unique fingerprint.

  • Cite this

    Wen-Ho, C., Shih-Ku, L., Jann, M. W., Lam, Y. W. F., Teng-Yi, C., Chao-Tsao, C., Wei-Herng, H., & Eng-Kung, Y. (1989). Pharmacodynamics and pharmacokinetics of haloperidol and reduced haloperidol in schizophrenic patients. Biological Psychiatry, 26(3), 239-249. https://doi.org/10.1016/0006-3223(89)90036-X