Fluoroquinolones may prolong QTc interval (avoid use in history of QTc prolongation, uncorrected hypokalemia, hypomagnesemia, or concurrent administration of other medications known to prolong QT interval). CNS stimulation (tremor, restlessness, confusion, and very rarely hallucinations or seizures) might occur (use with caution in CNS disorders). Possible disordered glucose regulation (hypoglycemia or hyperglycemia). Severe hepatotoxicity (including acute hepatitis and fatalities) reported. Severe hypersensitivity reactions, including anaphylaxis, occurred. Use of quinolones linked to peripheral neuropathy (rare). Might cause moderate-to-severe phototoxicity reactions. Prolonged use may result in fungal or bacterial superinfection, including C. difficile-associated diarrhea and pseudomembranous colitis. Reports of tendon inflammation and/or rupture with quinolone antibiotics (increased risk with concurrent corticosteroids, organ transplant recipients, and in patients >60 years of age). Some quinolones may exacerbate myasthenia gravis, use with caution (rare, potentially life-threatening weakness of respiratory muscles might occur). Use with caution in renal impairment or rheumatoid arthritis (might increase risk of tendon rupture). Use with caution in individuals at risk of seizures. Adverse effects (e.g. hepatotoxicity, tendon rupture, QT changes) might be increased in the elderly. Hemolytic reactions may (rarely) occur in latent or actual G6PD deficiency. Systemic use only recommended in children <18 years of age for prevention of inhalational anthrax (postexposure). Increased incidence of musculoskeletal disorders (e.g. arthralgia, tendon rupture) observed in children. Ophthalmic solution for topical use only.