Penetration of ciprofloxacin and fleroxacin into biliary tract.

Forty patients with chronic cholecystitis or cholelithiasis were prospectively randomized for therapy with either ciprofloxacin or fleroxacin to study the penetration of these two agents into gallbladder tissue, plasma, and bile. Patients received a 3-day course of ciprofloxacin (500 mg twice a day) or fleroxacin (400 mg once daily) and were subdivided into four groups reflecting intraoperative sample collection at 4, 7, 14, and 25 to 26 h following the last quinolone dose. Mean concentrations in plasma for ciprofloxacin and fleroxacin at 4 and 25 to 26 h postdose were 2.5 and 10 micrograms/ml and 0.3 and 1.8 micrograms/ml, respectively. The concentrations of ciprofloxacin and fleroxacin in bile and gallbladder wall tissue at 25 to 26 h postdose were 4.5 and 8.6 micrograms/ml and 1.2 and 4.4 micrograms/ml, respectively. Both agents demonstrate rapid tissue penetration with persistence at levels appropriate for treatment of biliary pathogens.