title: Cortical bone concentrations of enrofloxacin in dogs.
abstract: Cortical bone concentrations of enrofloxacin were determined over time in dogs after SC administration of the drug. Nineteen healthy adult dogs were anesthetized and were given 2.5 or 5.0 mg of enrofloxacin/kg of body weight, SC. Serial serum and bone samples were obtained for determination of enrofloxacin concentrations at intervals until 8 hours after drug administration. Cortical bone samples were procured by surgical disarticulation of successive second phalanges. Additional cortical bone samples were taken from long bones in 4 dogs. Mean +/- SD peak serum enrofloxacin concentration was 0.54 +/- 0.10 micrograms/ml for the 2.5 mg/kg dosage and 0.97 +/- 0.34 micrograms/ml for the 5.0-mg/kg dosage. Serum concentration was significantly higher than bone concentration for each dosage. Mean peak bone concentrations reached 29% of peak serum values: 0.15 +/- 0.09 micrograms/g and 0.29 +/- 0.09 micrograms/g for 2.5-mg/kg and 5.0-mg/kg dosages, respectively. Serum concentration for the 5.0-mg/kg dosage was significantly greater than that for the 2.5-mg/kg dosage for all times, whereas bone concentrations for the 5.0-mg/kg dosage were significantly higher at all times after 180 minutes. For the duration of the study, cortical bone concentrations of enrofloxacin at either dosage exceeded the minimum inhibitory concentration (MIC) for the Enterobacteriaceae, but reliably exceeded the MIC for Staphylococcus sp only at the 5.0-mg/kg dosage.(ABSTRACT TRUNCATED AT 250 WORDS)
authors.affiliation: Department of Small Animal Medicine, College of Veterinary Medicine, University of Georgia, Athens 30602, USA.
authors.forename: J M
authors.initials: JM
authors.lastname: Duval
authors.forename: S C
authors.initials: SC
authors.lastname: Budsberg
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D000890:Anti-Infective Agents / Q000493:pharmacokinetics* / Q000627:therapeutic use; D001842:Bone and Bones / Q000378:metabolism*; D004283:Dog Diseases / Q000188:drug therapy / Q000378:metabolism; D004285:Dogs; D000077422:Enrofloxacin; D024841:Fluoroquinolones; D010019:Osteomyelitis / Q000188:drug therapy / Q000378:metabolism / Q000662:veterinary; D015363:Quinolones / Q000493:pharmacokinetics* / Q000627:therapeutic use
chemical_list: D000890:Anti-Infective Agents; D024841:Fluoroquinolones; D015363:Quinolones; D000077422:Enrofloxacin