Infection is still one of the leading causes of morbidity and mortality in severely burned patients. Evidence suggests that many of the responsible organisms are endogenous. Systemic antibiotic prophylaxis is not effective, and produces resistant strains of microorganisms. SDD has been postulated to be beneficial for controlling and decreasing infections in critically ill patients. Its efficacy in severely burned patients, however, remains controversial. In order to analyze the efficacy of selective decontamination of the digestive (SDD) tract, to decrease the bacterial colonization of the aerodigestive tract and burn wounds, and the incidence of septic complications in severely burned children, 23 pediatric patients affected of severe burns were prospectively randomized in a double-blinded study. Eleven patients received SDD (Polymyxin E, Tobramycin, and Amphotericin B), and 12 placebo. Demographics, hospital course, microbiology results, complications, infectious episodes, and serum levels of IL-1β, IL-6, IL-10, and TNF-α were compared to determine the efficacy of SDD. Colonization rates to the wound, sputum, nasogastric aspirates, and feces were similar. Pneumonia, sepsis and other complications had similar incidence in both groups. Serum levels of all cytokines studied were also comparable, suggesting a similar inflammatory status in all patients, regardless of the treatment received. Patients in the SDD group, however, had a significantly higher incidence of diarrhea (P=0.003). We can conclude that selective decontamination of the digestive tract with Polymixin E, Tobramycin and Amphotericin B is not effective to decrease bacterial colonization and infectious episodes in severely burned pediatric patients.