title: Liquid chromatographic determination of reduced haloperidol and haloperidol concentrations in packed red blood cells from humans.
abstract: Haloperidol (H) is a neuroleptic drug that has one known biologically active metabolite, reduced haloperidol (RH). A liquid chromatographic method is described for the determination of both compounds in human red blood cell (RBC) samples. The drugs were extracted into hexane at high pH and back-extracted into 0.1M HCl. The acid solution was then analyzed by reversed-phase chromatography under the following conditions: column was ultrasphere ODS; eluant was acetonitrile:0.085M phosphate buffer (30:70), final pH was 3.5, flow rate was 2 mL/min; detection was by light absorption at 246 nm for H and 220 nm for RH. The minimum limits of quantitation for H and RH were 0.25 and 0.1 ng/mL of packed RBC respectively. For six selected patients on 10 or 20 mg per day of oral haloperidol the RBC to plasma concentration ratios for RH and H were 2.20 +/- 0.9 (SD) and 0.81 +/- 0.26, respectively. The data indicate that RH is more concentrated in RBC than in plasma.
authors.affiliation: Geriatric Research, Education and Clinical Center, Veterans Administration Medical Center, Minneapolis, Minnesota 55417.
authors.forename: G T
authors.initials: GT
authors.lastname: Vatassery
authors.forename: L A
authors.initials: LA
authors.lastname: Herzan
authors.forename: M W
authors.initials: MW
authors.lastname: Dysken
mesh_terms: D002851:Chromatography, High Pressure Liquid; D004912:Erythrocytes / Q000032:analysis*; D006220:Haloperidol / Q000097:blood*; D006801:Humans; D010084:Oxidation-Reduction
chemical_list: D006220:Haloperidol