title: Pharmacokinetic and pharmacodynamic properties of enrofloxacin in southern crested caracaras (Caracara plancus).
abstract: To determine the dosage of enrofloxacin in southern crested caracaras (Caracara plancus), plasma concentrations of enrofloxacin were measured by high-performance liquid chromatography after intravenous (IV) (5 mg/kg) and intramuscular (IM) (10 mg/kg) administration. This compound presented a relatively high volume of distribution (2.09 L/kg), a total body clearance of 0.24 L/kg x h, and a long permanence as shown by an elimination half-life of 7.81 hours after IV administration and a terminal half-life of 6.58 hours after IM administration. The areas under the concentration-time curves (AUC) were 21.92 and 34.38 microg x h/mL for IM and IV administration, respectively. Enrofloxacin was rapidly absorbed after IM administration with a time to reach maximum concentration of 0.72 hours and bioavailability of 78.76%. After IM administration, the peak drug concentration (C(max)) was 3.92 microg/mL. Values of minimum inhibitory concentration (MIC), C(max), and AUC have been used to predict the clinical efficacy of a drug in treating bacterial infections, with a C(max)/MIC value of 10 and an AUC/MIC ratio of 125-250 associated with optimal bactericidal effects. By using the study data and a MIC breakpoint of 0.25 microg/mL, values of C(max)/MIC were 13.74 and 15.94 and for AUC/MIC were 90.73 and 139.63, for the IV and IM routes respectively. For the treatment of infectious diseases caused by microorganisms with MIC < or = 0.25 microg/mL, the calculated optimal dosages were 7.5 and 9.5 mg/kg q24h by the IV and IM routes, respectively. For less susceptible bacteria, a dose increase should be evaluated. To treat caracara by the IV route against microorganisms with MIC < or = 0.25 microg/mL, the dose should be higher than the 5 mg/kg used in our study, but possible side effects derived from an increase in the IV dose and efficacy in sick birds should be assessed.
authors.affiliation: Pharmacology Department, FCV, University of Buenos Aires, Chorroarin 280, 1427, Argentina.
authors.forename: Samanta
authors.initials: S
authors.lastname: Waxman
authors.affiliation: Pharmacology Department, FCV, University of Buenos Aires, Chorroarin 280, 1427, Argentina.
authors.forename: Ana Paula
authors.initials: AP
authors.lastname: Prados
authors.affiliation: Pharmacology Department, Universidad Complutense de Madrid, Av. Puerta de Hierro s/n, 28040, Spain.
authors.forename: Julio
authors.initials: J
authors.lastname: de Lucas
authors.affiliation: Pharmacology Department, Universidad Complutense de Madrid, Av. Puerta de Hierro s/n, 28040, Spain.
authors.forename: Manuel Ignacio
authors.initials: MI
authors.lastname: San Andres
authors.affiliation: Reserva Ecológica Costanera Sur, T. A. Rodriguez 1550, 1107, Buenos Aires, Argentina.
authors.forename: Juan Carlos
authors.initials: JC
authors.lastname: Sassaroli
authors.affiliation: Ecoepidemiology Laboratory, FCEN, UBA, C. Universitaria, 1428 Buenos Aires, Argentina.
authors.forename: Marcela
authors.initials: M
authors.lastname: Orozco
authors.affiliation: Ecological Park "El Puma", MEYRNR, Candelaria, 3308 Misiones, Argentina.
authors.forename: Hernán
authors.initials: H
authors.lastname: Argibay
authors.affiliation: Pharmacology Department, Universidad Complutense de Madrid, Av. Puerta de Hierro s/n, 28040, Spain.
authors.forename: Casilda
authors.initials: C
authors.lastname: Rodriguez
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000097:blood / Q000493:pharmacokinetics*; D019540:Area Under Curve; D001717:Birds / Q000097:blood*; D016123:Campylobacter jejuni / Q000187:drug effects; D002939:Ciprofloxacin / Q000097:blood / Q000378:metabolism / Q000493:pharmacokinetics; D000077422:Enrofloxacin; D004926:Escherichia coli / Q000187:drug effects; D024841:Fluoroquinolones / Q000097:blood / Q000493:pharmacokinetics*; D006207:Half-Life; D008826:Microbial Sensitivity Tests
chemical_list: D000900:Anti-Bacterial Agents; D024841:Fluoroquinolones; D000077422:Enrofloxacin; D002939:Ciprofloxacin