History of CNS disorders, pseudomembranous colitis, superinfection, severe renal dysfunction, epilepsy, G6PD deficiency, myasthenia gravis, patients with QT prolongation, uncorrected electrolyte disturbances, bradycardia, or pre-existing cardiac disease. Avoid exposure to strong sunlight or sunlamps during treatment. Discontinue treatment if patients experience tendon pain, inflammation or rupture; subsequent use of fluoroquinolones in these patients is not recommended. Avoid in MRSA infections due to high risk of resistance. Ensure adequate fluid intake to reduce risk of crystalluria.