For bacterial conjunctivitis & blepharitis: Instill 1 drop in the affected eye(s) 3 times a day for 7 days. For keratitis: Instill higher doses in the affected eye(s) as per needed or directed by the physicians. For surgical prophylaxis: Instill 1 drop in the affected eye(s) every 10 minutes for a total 4 doses beginning 1 hour before cataract surgery.