Antimicrobial therapy is the standard of care for the unusual man with true chronic bacterial prostatitis but does not have much of a role in the treatment of men with nonbacterial prostatitis. The fluoroquinolone antibiotics given for 2 to 4 weeks will cure about 70% of chronic bacterial infections of the prostate. If this treatment fails, the symptomatic manifestations of the infections can almost always be eliminated with suppressive antimicrobial therapy using trimethoprim-sulfamethoxazole, a fluoroquinolone antibiotic, or nitrofurantoin.