Distribution of ciprofloxacin in ascitic fluid following administration of a single oral dose of 750 milligrams.

The penetration of ciprofloxacin into the ascitic fluid of eight patients was studied. Serum and ascitic fluid samples were obtained before and at 1, 2, 3, 6, and 12 h following administration of a single oral dose of 750 mg. Peak levels (mean +/- standard deviation) were 4.0 +/- 0.7 micrograms/ml in serum and 2.6 +/- 0.6 micrograms/ml in ascitic fluid; the areas under the curve (0 to 12 h) were 29.1 +/- 6.5 micrograms.h/ml in serum and 20.7 +/- 5.0 micrograms.h/ml in ascitic fluid. The concentrations that were achieved are well above the MICs of ciprofloxacin for the members of the family Enterobacteriaceae that cause spontaneous bacterial peritonitis.