Pharmacokinetics of ciprofloxacin in carp, African catfish and rainbow trout

The plasma disposition of ciprofloxacin was studied in carp, African catfish and trout after intravenous (IV) and intramuscular (IM) administration at a dose rate of 15 mg/kg. Pharmacokinetic analysis of IV data showed that ciprofloxacin was well distributed (distribution volume Vd(area): 3.08-5.59 litre/kg) and exhibited a similar elimination half-life of about 14 h in these 3 fish species. After IM administration to carp and trout a rapid absorption was noticed; the maximum ciprofloxacin plasma concentrations (mean: 3.49 and 2.37 micrograms/ml, respectively), were achieved within 1 h after injection. At the dose level applied, ciprofloxacin has potential therapeutic value for 2-5 days especially against gram-negative bacterial fish pathogens.