Human prostatic tissue concentrations of rosoxacin.

The corresponding concentrations of rosoxacin in serum (S) and prostatic tissue (PT) were determined in 15 patients undergoing transurethral resection of the prostate because of benign prostatic hyperplasia. Rosoxacin concentrations were determined employing both bioassay and a high-pressure liquid chromatography procedure, with excellent correlation between the two methods. Two dosage schedules were followed, resulting in median serum concentrations of 3.6 and 5.8 microgram/ml, respectively. The ratio of PT/S was found to be fairly constant and surprisingly high, the median values being 0.46 and 0.56. These results indicate that concentrations of rosoxacin are obtained in prostatic interstitial fluid in the range of the minimal inhibitory concentrations for most of the gram-negative pathogens causing bacterial prostatitis and urinary tract infections. Acceptable drug concentrations also were determined in urine and cerebrospinal fluid. The results obtained in this study warrant further clinical trials for rosoxacin in the treatment of bacterial prostatitis and urinary infections.