Disposition kinetics and urinary excretion of ciprofloxacin in goats following single intravenous administration

Disposition kinetics and urinary excretion of ciprofloxacin in goats following single intravenous administration

We evaluated the pharmacokinetics of ciprofloxacin in serum (n = 6) and urine (n = 4) in goats following a single intravenous administration of 4 mg/kg body weight. The serum concentration-time curves of ciprofloxacin were best fitted by a two-compartment open model. The drug was detected in goat serum up to 12 h. The elimination rate constant (<FONT FACE="Symbol">b) and elimination half-life (t<SUB>1/2</SUB><FONT FACE="Symbol">b) were 0.446 &#177; 0.04 h and 1.630 &#177; 0.17 h, respectively. The apparent volume of distribution at steady state (Vd<SUB>ss</SUB>) was 2.012 &#177; 0.37 l/kg and the total body clearance (Cl<SUB>B</SUB>) was 16.27 &#177; 1.87 ml/min/kg. Urinary recovery of ciprofloxacin was 29.70% &#177; 10.34% of the administered dose within 36 h post administration. <I>In vitro</I> serum protein binding was 41% &#177; 13.10%. Thus, a single daily intravenous dose of 4 mg/kg is sufficient to maintain effective levels in serum and for 36 h in urine, allowing treatment of systemic, Gram-negative bacterial infections and urinary tract infections by most pathogens.