We investigated the efficacy and safety of norfloxacin 0.3% ophthalmic solution in 120 patients with bacterial conjunctivitis or blepharitis. Patients were selected for the study if they showed conjunctival hyperemia and at least three of the following criteria: a) symptoms of a surface ocular infection; b) a purulent discharge; c) crusting of the eyelids, and d) thickened, red lid margins. After taking a specimen for culture from the conjunctiva or skin-lash margin, the test drug was administered to the infected eye every two hours for one day, then 4 times daily for one week. Of the 120 patients who entered the study, 84.1% were cured. No serious adverse reactions occurred.