title: Intravenous infusion of electrolyte solution changes pharmacokinetics of drugs: pharmacokinetics of ampicillin.
abstract: The pharmacokinetics of ampicillin in dogs was determined after intravenous (i.v.) bolus and constant rate infusion. Ampicillin was administered to six beagle dogs as an i.v. bolus at 20 mg/kg and as a constant rate i.v. infusion (CRI) at 20 mg/kg during 8 h (0.042 mL/min/kg) in Ringer's lactate (Hartmann's) solution. The concentrations were determined by an LC/MS/MS method. After i.v. bolus, ampicillin total body clearance, apparent volume of distribution at steady-state, mean residence time (MRT), and half-life were 4.53 ± 0.70 mL/min/kg, 0.275 ± 0.044 L/kg, 61 ± 13 min, and 111 (85-169) min, respectively. The corresponding parameters calculated after CRI were 13.5 ± 1.06 mL/min/kg, 0.993 ± 0.415 L/kg, 73 ± 27 min, and 49 (31-69) min. Ampicillin concentration decreased by 30% in the Ringer's lactate infusion solution mostly during the first hour after preparation of the solution. Constant rate infusion of Ringer's lactate solution during 8 h caused significant changes in ampicillin pharmacokinetics. The results suggested that special attention should be given to drug pharmacokinetics when co-administered intravenously with electrolyte solutions.
authors.affiliation: National Residue Control Laboratory, Kimron Veterinary Institute, Veterinary Services, Ministry of Agriculture, Beit Dagan, Israel.
authors.forename: M
authors.initials: M
authors.lastname: Britzi
authors.forename: Y
authors.initials: Y
authors.lastname: Mazon
authors.forename: E
authors.initials: E
authors.lastname: Lavy
authors.forename: S
authors.initials: S
authors.lastname: Soback
mesh_terms: D000667:Ampicillin / Q000008:administration & dosage / Q000097:blood / Q000493:pharmacokinetics*; D000818:Animals; D000900:Anti-Bacterial Agents / Q000008:administration & dosage / Q000097:blood / Q000493:pharmacokinetics*; D019540:Area Under Curve; D004285:Dogs / Q000097:blood*; D004347:Drug Interactions; D004573:Electrolytes / Q000008:administration & dosage*; D006207:Half-Life
chemical_list: D000900:Anti-Bacterial Agents; D004573:Electrolytes; D000667:Ampicillin