General Principles

• Fluoroquinolones exert their bactericidal effect by inhibiting bacterial enzymes DNA gyrase and topoisomerase IV, which are critical for DNA replication. These antibiotics are well absorbed orally, with serum concentrations that approach those of parenteral administration, making them ideal candidates for switching from IV to PO formulations.
• Concomitant administration with aluminum- or magnesium-containing antacids, sucralfate, bismuth, oral iron, oral calcium, oral zinc, and metallic cation–containing enteral nutrition preparations can markedly impair absorption of oral fluoroquinolones.