Twenty-four patients suffering from prostate hyperplasia were given venous injections of CDZM of either 1 or 2 g at specific intervals (30 min, 1, 2 and 4 hr) before surgery. Blood samples from the injected vein and tissue samples from the prostate were subsequently taken. In this study, the concentrations of CDZM in the prostate tissue (P) and in serum (S), as well as the ratio of the tissue to serum concentrations (P/S) were determined. In patients given 1 g injections, P ranged from 5.26-48.10 micrograms/g, while S ranged from 25.40-130.00 micrograms/ml and P/S ranged from 12.6-37.0%. In the patients given 2 g injections, P ranged from 9.40-49.20 micrograms/g, S ranged from 62.30-234.00 micrograms/ml and P/S ranged from 9.3-29.1%. CDZM exhibited excellent transmigration to the prostate tissue. Inflammatory bacteria present in prostatitis and urinary tract infections are generally those of E. coli, Proteus sp., but because the P range was much higher than the ratio of MIC, CDZM is expected to be useful against infections in the field of urology.