In patients with alcoholic cirrhosis, the pharmacokinetics of the fluoroquinolones were variously altered. The kinetics of ciprofloxacin were slightly modified in patients with mild or moderate impairment. Ofloxacin kinetics were influenced by renal dysfunction encountered in patients with ascites. Pefloxacin kinetics were markedly modified with wide variations in elimination among patients. Ascitic penetration of ofloxacin and pefloxacin was excellent. Since no relationship between ofloxacin or pefloxacin kinetics and the usual liver function tests was found, recommended dosage regimens in cirrhotic patients have to be controlled by monitoring plasma drug levels during treatment.