Active Ingredient: Norfloxacin
The study also explored the effects of antimicrobial treatment on drug resistance. Methods Study population.
The study was conducted in 4 food factories in an area of Thailand where NTS is endemic.
The workers are routinely checked for enteric pathogens, and Salmonella carriers are commonly treated with an antimicrobial regimen.
Informed consent was obtained from each worker before a pretreatment rectal swab specimen was obtained.
NTS-positive workers were offered participation in the trial.
Pregnant or breast-feeding women and persons with diarrhea, any illness, or history of quinolone or macrolide intolerance were excluded.
Study design and treatment regimens. The study was a randomized, double-blind, placebo-controlled trial.
Three 5-day regimens were used, as follows: 1 two 200-mg norfloxacin Lexinor; Astra tablets twice per day, 2 two 250-mg azithromycin Zithromax, Pfizer tablets in the morning plus 2 azithromycin placebo tablets in the evening, and 3 placebo.
One-half of the third group received 2 placebo tablets twice per day in lieu of norfloxacin, and one-half received 2 placebo tablets twice per day in lieu of azithromycin.
Each trial participant was given an identification number. Participants at each factory were randomly assigned by computer in a 1: 1: 1 ratio to receive 1 of the 3 regimens. The participants assigned to receive placebo were randomized to receive either norfloxacin placebo or azithromycin placebo, but data for these persons were combined into 1 placebo group for analysis.
Each participant's identification number was placed on a set of 2 opaque envelopes containing the tablets for the individual regimen; one envelope was for the morning dose, and the other was for the evening dose. The treatment was begun 5 days after the pretreatment rectal swab specimen was obtained.
The research assistants who gave medicine to the participants had been informed about the medication procedure but were not involved in any other part of the trial.
Microbiological investigation. Three research assistants responsible for obtaining a rectal swab followed a standardized technique. To preserve randomization within each trial, we included a dummy variable for each study.