Pharmacokinetics of gatifloxacin in broiler chickens following intravenous and oral administration

1. The pharmacokinetics of gatifloxacin were investigated following intravenous and oral administration of a single dose at a rate of 10 mg/kg body weight in broiler chicks. 2. Drug concentration in plasma was determined using High Performance Liquid Chromatography with ultraviolet detection on samples collected at frequent intervals after drug administration. 3. Following intravenous administration, the drug was rapidly distributed (t1/2α: 0·33 ± 0·008 h) and eliminated (t1/2β: 3·62 ± 0·03 h; ClB: 0·48 ± 0·002 l/h/kg) from the body. 4. After oral administration, the drug was rapidly absorbed (C max: 1·74 ± 0·024 µg/mL; T max: 2 h) and slowly eliminated (t1/2β: 3·81 ± 0·07 h) from the body. The apparent volume of distribution (Vd(area)), total body clearance (ClB) and mean residence time (MRT) were 3·61 ± 0·04 l/kg, 0·66 ± 0·01 l/h/kg and 7·16 ± 0·08 h, respectively. The oral bioavailability of gatifloxacin was 72·96 ± 1·10 %. 5. Oral administration of gatifloxacin at 10 mg/kg is likely to be highly effic...