title: Effects of time of administration and posture on the pharmacokinetics of cefprozil.
abstract: The effects of time of administration, sleep and posture on the pharmacokinetics of cefprozil were evaluated in a single-dose 3-way crossover study. After a 6-hour fast, 12 healthy male volunteers received oral cefprozil 250mg at 1200h (treatment A), 1200h (treatment B) and 2400h (treatment C) with a 7-day washout interval between each treatment. During the study period, volunteers receiving treatment A remained in a sitting/standing position or were ambulatory, those receiving treatment B were in the supine position, and those receiving treatment C were sleeping. Blood samples were taken over an 8-hour period and the plasma samples were analysed for the concentrations of cefprozil by a high performance liquid chromatography-ultraviolet method. Plasma concentration vs time data were analysed using noncompartmental analysis methods. Mean peak plasma concentrations (Cmax) were 4.51, 5.02 and 4.91 mg/L for treatments A, B and C, respectively. Corresponding mean values of the area under the plasma concentration-time curve (AUC(0-infinity)) were 12.6, 12.6 and 14.2 mg/L.h, respectively. The mean half-life (t1/2) values were 1.30, 1.23 and 1.50 hours for treatments A, B and C, respectively. Mean AUC(0-infinity), Cmax and t1/2 values following treatment B were not significantly different from those of treatment A. However, the mean AUC(0-infinity) and t1/2 values of cefprozil following treatment C were significantly greater than those of either treatment A or B. The mean Cmax value following treatment C was not significantly different than that of either treatments A or B. From these results, it was concluded that posture has no effect on the pharmacokinetics of cefprozil.(ABSTRACT TRUNCATED AT 250 WORDS)
authors.affiliation: Department of Metabolism and Pharmacokinetics, Bristol-Myers Squibb Pharmaceutical Research Institute, Bristol-Myers Squibb Company, Syracuse, New York.
authors.forename: W C
authors.initials: WC
authors.lastname: Shyu
authors.forename: C R
authors.initials: CR
authors.lastname: Gleason
authors.forename: R H
authors.initials: RH
authors.lastname: Barbhaiya
mesh_terms: D000328:Adult; D002511:Cephalosporins / Q000008:administration & dosage / Q000493:pharmacokinetics*; D002851:Chromatography, High Pressure Liquid; D004334:Drug Administration Schedule; D006207:Half-Life; D006801:Humans; D008297:Male; D011187:Posture / Q000502:physiology*; D012890:Sleep / Q000502:physiology; D013997:Time Factors; D000097670:Cefprozil
chemical_list: D002511:Cephalosporins; D000097670:Cefprozil