What Role do Fluoroquinolone Antimicrobial Agents Play in Cardiac Dysfunction and Altered Glycemic Control?

This article focuses on the development of 2 major adverse drug events associated with some fluoroquinolone antimicrobial agents, specifically cardiac and glycemic effects. Cardiac dysfunction, including corrected QT (QTc) interval prolongation and torsades de pointes, has been linked to the administration of fluoroquinolones. The first indication of QTc prolongation was reportedwith sparfloxacin, and since that time, it has been associated with a number of other fluoroquinolones, leading to the assumption that this is a general class effect. Fluoroquinolone-associated effects on cardiac conduction appear more likely to occur in patients with underlying cardiac diseases, those with electrolyte abnormalities, and those coadministered antiarrhythmics and other QTc-prolonging drugs. Some fluoroquinolone agents have also been associated with alterations in glycemic control. Hypoglycemia and hyperglycemia have been reported with many of the currently available agents. Risk factors for aberrations in glucose homeostasis include noninsulindependent diabetes mellitus, increased age, impaired renal function, and the concomitant use of oral hypoglycemic agents. The widespread use of fluoroquinolones highlights the need for clinicians to consider predisposed populations and use caution when selecting antimicrobial therapies.