The pharmacokinetics of the biliary excretion of ciprofloxacin.

The pharmacokinetics of ciprofloxacin excretion have been studied in 54 patients undergoing biliary and pancreatic operations with and without obstruction of the common bile duct. High concentrations were achieved in common duct bile within 20 minutes of intravenous injection and persisted for over 3 hours after 100 mg and for over 8 hours after 200 mg. The concentration of ciprofloxacin in the bile of functioning gall bladders was much greater than that in the common duct bile. Remarkably, it was identified in therapeutic concentrations in the bile of obstructed ducts. This and the rapid fall from initially high venous concentrations probably reflect diffusion from the circulation as a result of the exceptional tissue penetration. A unique feature of this study was the finding of clinically significant concentrations in the bile of obstructed ducts. Two patients developed wound infection and no side effects were observed. The broad spectrum antibiotic ciprofloxacin has potential as a useful agent for prophylaxis in biliary surgery maintaining biliary and venous concentrations in excess of the MIC90 for most biliary pathogens for more than 8 hours.