The determination of the steady-state pharmacokinetic profile of fluphenazine decanoate by gas chromatography/mass spectrometry detection.
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.
Glazer
W M
WM
Yale University School of Medicine, New Haven, CT.
Friedhoff
L T
LT
Marder
S R
SR
Brown
W A
WA
D000328:Adult; D002908:Chronic Disease; D004305:Dose-Response Relationship, Drug; D004334:Drug Administration Schedule; D005260:Female; D005476:Fluphenazine / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000493:pharmacokinetics; D008401:Gas Chromatography-Mass Spectrometry; D006801:Humans; D007273:Injections, Intramuscular; D008297:Male; D008875:Middle Aged; D011388:Prolactin / Q000097:blood; D012559:Schizophrenia / Q000097:blood* / Q000188:drug therapy; D012565:Schizophrenic Psychology
D011388:Prolactin; C011825:fluphenazine depot; D005476:Fluphenazine