Safety and tolerability of commonly prescribed oral antibiotics for the treatment of respiratory tract infections.

Recent data suggest that adverse events (AEs) associated with the use of antimicrobial drugs are a major safety concern, with antibiotics implicated in a significant proportion (approximately 20%) of all drug-related emergency department visits in the United States. Although most of these visits are attributable to allergic reactions (79%), certain commonly prescribed antibiotics are notable contributors to conditions that range in nature from gastrointestinal to neurologic and/or psychiatric--particularly after ED visits are adjusted per outpatient prescription visits. This article reviews medically significant AEs of agents included in the major antimicrobial classes--AEs that may be underappreciated by general practitioners. Considerable attention is devoted to the fluoroquinolone agents. Also discussed are the assessment procedures of regulatory agencies in Europe and the United States that are in place to evaluate antimicrobial safety more accurately. Offsetting potential risks and benefits associated with currently available antimicrobials in a climate in which new agents are desperately needed to combat continually evolving multiresistant pathogens remains an interesting dilemma in antimicrobial therapy. Copyright 2010 Elsevier Inc. All rights reserved.