Intraprostatic concentration of ciprofloxacin and its activity against urinary pathogens.

The in-vitro activity of ciprofloxacin against 376 urinary pathogens was determined. The minimal inhibitory concentrations for 90% of the Enterobacteriaceae were 0.03-0.23 mg/l, for Pseudomonas aeruginosa 0.37 mg/l, for Streptococcus faecalis 0.75 mg/l and for Staphylococcus aureus 0.92 mg/l. A 100 mg dose of ciprofloxacin was administered intravenously to 25 patients undergoing prostatectomy. The concentrations in prostate and serum were measured at different intervals. Peak levels in prostate were 3.0 micrograms/g attained 20 min after administration. Peak serum levels were 1.2 mg/l attained 20 min after administration. Serum and prostate elimination was slowly. The overall serum: prostate ratio 1:2.1.