Trimethoprim-polymyxin B sulphate ophthalmic ointment versus chloramphenicol ophthalmic ointment in the treatment of bacterial conjunctivitis--a review of four clinical studies. The Trimethoprim-Polymyxin B Sulphate Ophthalmic Ointment Study Group.

Five hundred and twenty-eight patients with a clinical diagnosis of bacterial conjunctivitis were enrolled in four randomized, double-blind, parallel studies. Patients were treated with trimethoprim-polymyxin B sulphate (TP) or chloramphenicol ophthalmic ointments, four times a day for seven days in three studies, and three times a day for five days in one. Data suitable for evaluation of efficacy and safety were obtained from 448 patients. The results of each study were analysed separately and indicated that both treatments were effective and well tolerated and that there were no statistically significant differences between them. However, in three studies, efficacy trends generally favoured TP ophthalmic ointment and in one study efficacy trends favoured chloramphenicol ophthalmic ointment. A wide range of pathogenic or potentially pathogenic organisms was isolated, with Haemophilus influenzae being the most prevalent.