A 5-day, once-daily regimen of Levaquin (levofloxacin, from Ortho-McNeil) has been approved for the treatment of complicated urinary tract infections and acute pyelonephritis. This quinolone antibiotic is already indicated for the short-course treatment of community-acquired pneumonia and acute bacterial sinusitis. Levaquin is also used to treat a variety of bacterial infections caused by susceptible pathogens.