In an open study, 70 patients with uncomplicated anogenital Neisseria gonorrhoeae infection were evaluated to determine the efficacy and safety of a single oral dose of norfloxacin (800 mg). Norfloxacin cured all 31 male urethral and 25 endocervical infections. All 63 isolates of N. gonorrhoeae tested were inhibited by 0.05 microgram of norfloxacin per ml.