Fluoroquinolones: Dosage/Route: Adult: 250-750 mg/d PO or intravenous (IV); reduce dose in renal impairment After exposure to anthrax: 500 mg/d PO or IV for 60 d Usual Indications: Treatment of respiratory, urinary tract, skin, and sinus infections caused by susceptible gram-negative bacteria in adults; treatment after exposure to anthrax