The efficacy and safety of antibiotic combination therapy for infections caused by Gram-positive and Gram-negative organisms.

INTRODUCTION: Antibiotic combination therapy is often used to improve clinical efficacy in patients where a given therapy is thought to have limitations when used alone. However, the use of any antibacterial and perhaps more so with combination therapy comes with inherent risks. Herein the authors have evaluated both the risks and the benefits associated with the use of combination therapy. AREAS COVERED: Articles relating to the study of combination therapy were included by multiple Medline searches using relevant search terminology. Resultant publications included study by both in vitro and in vivo methodologies with clinical data coming from both observational and randomized studies. EXPERT OPINION: The majority of the data evaluating combination therapy were determined using in vitro techniques or animal models of infection. Through analyses of this information, coupled with the available clinical data, albeit limited, it is possible to identify a number of clinical situations where combination therapy can be supported. When used appropriately at optimal doses, combination therapy may offer an excellent opportunity to maximize clinical outcomes, particularly in the face of antibacterial resistance. Therefore, clinicians should evaluate carefully the risks and the potential benefits before adding additional antibiotics to standard single-drug therapies.