Effect of induced pyrexia on the disposition kinetics of ciprofloxacin in dogs.

Ciprofloxacin was administered intravenously @5 mg/kg body weight to six healthy dogs. After a washout period of two weeks, fever was induced by injecting Escherichia (E) coli endotoxin. Ciprofloxacin was administered again. Blood samples were collected at various time intervals and analyzed for ciprofloxacin with HPLC. The kinetic analysis revealed the volume of distribution in healthy vs. febrile dogs as 2.12 +/- 0.32 vs. 1.79 +/- 0.43 L/Kg, respectively. The elimination half life was 2.23 +/- 0.78 and 2.07 +/- 0.74 hours in healthy and febrile dogs, respectively. Similarly, dogs under healthy and febrile conditions showed comparable total plasma clearance of 0.66 +/- 0.06 and 0.60 +/- 0.07 L/Kg/h, respectively. All these and other investigated kinetic parameters were statistically non significant. This study concludes that the pharmacokinetic behavior of ciprofloxacin is similar under healthy and febrile conditions. Thus, the kinetic studies of fluoroquinolones conducted in normal/healthy animals may be used to depict the pharmacokinetic parameters in diseased animals.