title: Effect of standard breakfast on drug absorption and multiple-dose pharmacokinetics of ciprofloxacin.
abstract: Ciprofloxacin was administered to 10 volunteers, who received seven oral doses of 250 mg each at 12-h intervals. Volunteers alternately fasted (F) or received a standard breakfast (B) before the morning dose. Pharmacokinetic parameters were derived from high-pressure liquid chromatography data from samples taken after the first and seventh doses and were analyzed in addition for differences caused by food intake. A significant (P less than 0.05) influence of the standard breakfast on the time to the peak was observed. Peak levels (+/- standard deviation) after the first and seventh doses averaged F (fasting): 1.35 +/- 0.17, B (breakfast): 1.02 +/- 0.28 micrograms/ml, and F: 1.41 +/- 0.32, B: 1.17 +/- 0.5 micrograms/ml, respectively. Mean trough concentrations after the first and seventh doses were F: 0.10 +/- 0.03, B: 0.14 +/- 0.03 micrograms/ml, and F: 0.16 +/- 0.05, B: 0.14 +/- 0.04 microgram/ml, respectively. As with the peak, trough concentrations were not affected significantly by food intake or by accumulation over the study period. Breakfast equally did not affect the terminal half-lives, which averaged F: 3.97 +/- 0.67, B: 4.35 +/- 0.88 h after the first dose and F: 4.64 +/- 0.91, B: 3.72 +/- 0.84 h after the seventh dose. Twelve-hour urinary recovery measured by high-pressure liquid chromatography averaged F: 31, B: 30% for the first dose and, in spite of a possible carry-over from the sixth dose, decreased to F: 25, B: 28% after the seventh dosing interval. When measured by bioassay, an increase of urinary recovery between the first dose (F: 38, B: 38%) and the seventh dose (F: 45, B: 45%) was observed. These differences suggest induction of drug metabolism with repeated doses. Ciprofloxacin was well tolerated by the volunteers.
authors.forename: B
authors.initials: B
authors.lastname: Ledergerber
authors.forename: J D
authors.initials: JD
authors.lastname: Bettex
authors.forename: B
authors.initials: B
authors.lastname: Joos
authors.forename: M
authors.initials: M
authors.lastname: Flepp
authors.forename: R
authors.initials: R
authors.lastname: Lüthy
mesh_terms: D000328:Adult; D000890:Anti-Infective Agents / Q000008:administration & dosage / Q000378:metabolism*; D002851:Chromatography, High Pressure Liquid; D002939:Ciprofloxacin; D005260:Female; D005502:Food; D006801:Humans; D007408:Intestinal Absorption; D007700:Kinetics; D008297:Male; D011804:Quinolines / Q000008:administration & dosage / Q000378:metabolism*
chemical_list: D000890:Anti-Infective Agents; D011804:Quinolines; D002939:Ciprofloxacin