Cephapirin concentrations in prostatic and seminal vesicle tissues

A 15 min i.v. infusion supplying either 1 or 2 g of sodium cephapirin was administered preoperatively to patients about to undergo either retropubic or transvesical prostatectomy. Tissue samples were obtained 30 min after the end of the infusion. Blood samples were obtained immediately before the start of the infusion and 30 min after the end of it. Cephapirin levels in the blood averaged 25.9 +/- 4.0 microgram/ml after the 1 g dose and 47.5 +/- 5.6 microgram/ml after the 2 g dose. Drug levels in prostatic tissue averaged 24.5 +/- 7.1 and 25.8 +/- 4.4 microgram/g for the 1 and 2 g doses, respectively. Levels in tissue taken from the seminal vesicle, often the focus of infection in bacterial prostatitis, averaged 12.5 +/- 2.3 and 44.8 +/- 14.9 microgram/g for the 1 and 2 g doses, respectively. These results suggest that bactericidal levels of cephapirin against sensitive organisms can readily be achieved in the prostate and seminal vesicles.