In studies conducted in seven countries, 392 persons with acute
diarrhea were enrolled and randomly assigned to one of three regimens. In order to compare the effectiveness of various
therapies for acute
gastroenteritis, patients were treated for five days with either
norfloxacin, 400 mg twice daily,
norfloxacin, 400 mg three times a day, or
trimethoprim/sulfamethoxazole, (160 mg/800 mg) twice daily. Clinical cure occurred in 89 percent (lower dose) and 91 percent (higher dose) of those treated with
norfloxacin, compared with 78 percent of those receiving
trimethoprim/sulfamethoxazole; cure rates in each treatment group were greater when the patient's stool contained fecal leukocytes. In 105 of 106 (99 percent) patients treated with either dose of
norfloxacin and in 49 of 52 (94 percent)
trimethoprim/sulfamethoxazole-treated subjects, the bacterial enteropathogen identified in the pretreatment stool was eradicated on the posttreatment specimen. Two percent (two patients) of those receiving the lower dose of
norfloxacin, 3 percent (two patients) of those receiving
trimethoprim/sulfamethoxazole, and 4 percent (three patients) of those receiving the higher dose of
norfloxacin experienced minor and transient adverse hematologic or blood chemistry reactions. In addition, mild cutaneous reactions that were attributed to the study medications developed in two patients receiving the higher dose of
norfloxacin and in three patients who received
trimethoprim/sulfamethoxazole. These studies indicate that
norfloxacin is safe and effective
therapy for bacterial
diarrhea.