A COMPARATIVE-STUDY OF THE DISTRIBUTION OF OFLOXACIN AND CIPROFLOXACIN IN PROSTATIC TISSUES AFTER SIMULTANEOUS ORAL INGESTION

Objectives To determine the levels of two quinolones, ofloxacin and ci profloxacin, potent broad-spectrum antibiotics with very good oral bio availability and low minimum inhibitory concentrations (MICs) for most pathogens, in the prostates of patients who underwent transurethral r esection of the prostate (TURF) after oral ingestion for surgical prop hylaxis. Patients and methods Twenty-eight patients with BPH requiring a TURF ingested 250 mg of bath drugs 2-4 h before operation. The leve ls of the drugs in the serum and prostate were measured using highperf ormance liquid chromatography and the levels of both drugs determined at the 6 and 9 o'clock positions in the prostate to examine any local Variations in drug concentration. Results Ofloxacin concentrations wer e significantly higher in the serum and prostatic tissues compared wit h ciprofloxacin for the same dose, but its penetrance into the prostat e was lower. This mainly reflected its higher oral bioavailability. Bo th drugs were present in concentrations 50% higher at the 6 o'clock th an at the 9 o'clock position but both exceeded the MICs for most Gram- negative organisms except Pseudomonas. Conclusion Ofloxacin has the ad vantage against ciprofloxacin of exceeding the MICs for Staphylococcus and Chlamydia. However, ciprofloxacin has the advantage of having pro state-to-serum ratios of unity, but for the same dose the prostatic co ncentrations of ofloxacin is significantly higher.