Bactericidal activity of norfloxacin and nine other urinary tract antibiotics against Gram-negative bacilli causing bacteriuria in chronically catheterized patients.

We compared the bactericidal activities of norfloxacin and nine other oral urinary tract antibiotics against 344 Gram-negative bacilli causing bacteriuria in chronically catheterized patients. Norfloxacin killed all organisms at 32 mg/l, 91% of isolates at 2 mg/l, and was the most active antibiotic tested.