title: A randomized, double-blind, placebo-controlled trial of rifaximin to prevent travelers' diarrhea.
abstract: BACKGROUND
  Travelers' diarrhea causes substantial morbidity and postinfectious irritable bowel syndrome.
  
  
  OBJECTIVE
  To evaluate nonabsorbable rifaximin for prevention of travelers' diarrhea.
  
  
  METHODS
  Randomized, double-blind, placebo-controlled clinical trial.
  
  
  METHODS
  Guadalajara, Mexico.
  
  
  METHODS
  U.S. students.
  
  
  METHODS
  On arrival in Guadalajara, Mexico, 210 U.S. adults received rifaximin (200 mg/d, 200 mg twice daily, or 200 mg 3 times daily) or placebo for 2 weeks.
  
  
  METHODS
  Participants were followed daily for 3 weeks for enteric disease and symptoms and daily for 5 weeks for drug side effects. Changes in intestinal coliform flora were studied.
  
  
  RESULTS
  Travelers' diarrhea developed in 14.74% of participants taking rifaximin and 53.70% of those taking placebo (rate ratio, 0.27 [95% CI, 0.17 to 0.43]). Rifaximin provided 72% and 77% protection against travelers' diarrhea and antibiotic-treated travelers' diarrhea, respectively (P < 0.001 for both), and all rifaximin doses were superior to placebo. In the groups that did not report travelers' diarrhea, rifaximin significantly reduced the occurrence of mild diarrhea (P = 0.02) and moderate and severe intestinal problems (P = 0.009 for pain or cramps; P = 0.02 for excessive gas). Rates of adverse events were comparable in the rifaximin and placebo groups. Minimal changes in coliform flora were found during rifaximin therapy.
  
  
  CONCLUSIONS
  Rifaximin safely prevented travelers' diarrhea in Mexico, where most cases are caused by diarrhea-producing Escherichia coli. A study is needed in Asia to determine whether rifaximin can prevent diarrhea caused by invasive bacterial pathogens.
  
  
  CONCLUSIONS
  Rifaximin prevents travelers' diarrhea with minimal changes in fecal flora, and more liberal chemoprophylaxis against this disease should be considered. Future studies should evaluate whether rifaximin is effective in preventing postinfectious irritable bowel syndrome.
authors.affiliation: University of Texas-Houston, Baylor College of Medicine, St. Luke's Episcopal Hospital, and M.D. Anderson Cancer Center, Houston, Texas 77030, USA. hdupont@sleh.com
authors.forename: Herbert L
authors.initials: HL
authors.lastname: DuPont
authors.forename: Zhi-Dong
authors.initials: ZD
authors.lastname: Jiang
authors.forename: Pablo C
authors.initials: PC
authors.lastname: Okhuysen
authors.forename: Charles D
authors.initials: CD
authors.lastname: Ericsson
authors.forename: Francisco Javier
authors.initials: FJ
authors.lastname: de la Cabada
authors.forename: Shi
authors.initials: S
authors.lastname: Ke
authors.forename: Margaret W
authors.initials: MW
authors.lastname: DuPont
authors.forename: Francisco
authors.initials: F
authors.lastname: Martinez-Sandoval
mesh_terms: D000328:Adult; D000900:Anti-Bacterial Agents / Q000009:adverse effects / Q000493:pharmacokinetics / Q000627:therapeutic use*; D019072:Antibiotic Prophylaxis; D003967:Diarrhea / Q000382:microbiology / Q000517:prevention & control*; D004311:Double-Blind Method; D004927:Escherichia coli Infections / Q000517:prevention & control*; D006801:Humans; D007408:Intestinal Absorption; D008800:Mexico; D010919:Placebos; D011446:Prospective Studies; D012294:Rifamycins / Q000009:adverse effects / Q000493:pharmacokinetics / Q000627:therapeutic use*; D000078262:Rifaximin; D014195:Travel; D016896:Treatment Outcome; D014481:United States
chemical_list: D000900:Anti-Bacterial Agents; D010919:Placebos; D012294:Rifamycins; D000078262:Rifaximin