The determination of the steady-state pharmacokinetic profile of fluphenazine decanoate by gas chromatography/mass spectrometry detection

Schizophr Res. 1992 Dec;8(2):111-7. doi: 10.1016/0920-9964(92)90026-2.

Abstract

This study uses the highly sensitive method of gas chromatography/mass spectrometry to compare the basic steady-state pharmacokinetic parameters of two fluphenazine decanoate formulations. Sixteen stable outpatients participated in a two-way crossover design study of the bioavailability of a new formulation of FPZ Dec, i.e., 10 mg/ml, to the standard 25 mg/ml formulation. When compared to a 1 ml injection of the standard formulation (25 mg/ml) over a two-week, steady-state period, we found bioequivalence as evidenced by similar mean areas under the curve (hrs x ng/ml). We did find that the injection volume of the same dose (2.5 ml of a 10 mg/ml formulation) results in a statistically significantly higher maximum serum level of parent fluphenazine. A tendency toward faster time to peak level was observed with the 10 mg/ml formulation but the difference was not statistically significant. Both of these differences are considered too small to be clinically significant. In a subgroup of 10 patients, pre-injection serum fluphenazine levels correlated significantly (Pearson r = 0.78, p < 0.05) with serum prolactin levels.

Publication types

  • Clinical Trial
  • Comparative Study
  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Adult
  • Chronic Disease
  • Dose-Response Relationship, Drug
  • Drug Administration Schedule
  • Female
  • Fluphenazine / administration & dosage
  • Fluphenazine / analogs & derivatives*
  • Fluphenazine / pharmacokinetics
  • Gas Chromatography-Mass Spectrometry*
  • Humans
  • Injections, Intramuscular
  • Male
  • Middle Aged
  • Prolactin / blood
  • Schizophrenia / blood*
  • Schizophrenia / drug therapy
  • Schizophrenic Psychology*

Substances

  • Prolactin
  • fluphenazine depot
  • Fluphenazine