The aim of this study was to analyze the effect of using different antibiotics on the risk of acquiring a bacterial or fungal superinfection in hospital-acquired infections. A systematic review of the literature using the PubMed (Medline) database from January 1990 to December 2003 was performed. We selected only those studies with at least 25 patients in each arm in which the clinical efficacy of several antibiotics (third generation cephalosporins, fluorquinolones, piperacillin-tazobactam and carbapenems) were evaluated for the treatment of severe infections, and which specifically reported the rate of superinfection. The microorganisms most frequently implicated in the development of superinfection were: Candida spp. (42.3%), Enterococcus spp. (18.8%), enterobacteria (13.8%), Staphylococcus spp. (9.5%), Pseudomonas aeruginosa (6.6%), and Clostridium difficile (4.1%). The antibiotic most frequently related to superinfection was ciprofloxacin (38.1%), followed by cefotaxime (23.3%), imipenem (12%), meropenem (10.2%), and cefepime (6.1%). The lowest percentage of superinfection was observed with the use of piperacillin-tazobactam (5.4%).