Keith A. Rodvold, Pharm.D., FCP, FCCP
University of Illinois at Chicago, Colleges of Pharmacy and Medicine, Chicago, Illinois, USA

Fluoroquinolones are considered safe and well-tolerated anti-infective agents.
Among the newer agents (e.g., levofloxacin, moxifloxacin, gemifloxacin, gatifloxacin), the safety profiles continue to be evaluated. High-dose levofloxacin (750 mg once-daily) for short-course therapy or serious infections has demonstrated excellent tolerability and rates of adverse events comparable with other newer fluoroquolones. Recent studies evaluating moxifloxacin 400 mg once-daily have demonstrated a similar safety profile to levofloxacin 500 mg once-daily in elderly patients treated for community-acquired pneumonia. However, prolongation of the QTc interval occurs more frequently with moxifloxacin than with levofloxacin. Skin rash remains the major limitation in the safety profile of gemifloxacin and has restricted the duration of therapy to 5 or 7 days. Gemifloxacin-associated rash most commonly occurs after 8 to 10 days of therapy, in female patients younger than 40 years of age, and postmenopausal women receiving hormone replacement therapy. The increasing number of reports and higher incidence of hypoglycemia and hyperglycemia with gatifloxacin compared with other antibiotic therapy, including fluoroquinolones, has resulted in governmental agencies placing a contraindication on the use of gatifloxacin in patients with diabetes.