Formulation and Clinical Evaluation of Povidone-Iodine Ophthalmic Drop

Ophthalmia neonatorum is generally defined as conjunctivitis occurring within one month of life. The sources of this infection are environmental organisms or the organisms colonized in the birth canal. Untreated infection can cause blindness, especially if the corresponding organisms are Neisseria gonorrhoeae, or Chlamydia trachomatis. Povidone-iodine ophthalmic solution is an effective antibacterial agent with broad antibacterial and antiviral activity to which no bacterial resistance has been known. It is less expensive and less toxic than the agents currently used to prevent neonatal conjunctivitis. It turns the conjunctiva brown for a few minutes, a characteristic that can serve as an indicator of being properly applied. Because this preparation is not available in Iran, its formulation can be valuable. In this study, the povidone-iodine ophthalmic solution was prepared in concentration of 2.5%, and then required control parameters such as pH, self-preservation effect, tonicity, sterility, and chemical stability were studied. In this clinical study, one drop of povidone-iodine ophthalmic solution was instilled in each eye of 475 neonates within 30 minutes of birth. This study demonstrated that povidone-iodine in concentration of 2.5% is self-preservative against microbial contamination. The pH of solution was adjusted about 5 near to the pH of tear using sodium hydroxide 0.1 N and citric acid 0.5%, because in this pH povidone-iodine was more stable. Tonicity was measured according to an in vitro hemolytic method. Povidone-iodine 2.5% solution was packaged in amber color bottles, and after ensuring from its sterility, it was used in clinical study. Among the population studied, eye discharge was observed in 2.94 percent in comparison to the control group in which eye discharge was observed in 10.9 percent. In conclusion because of availability, low cast, and good clinical results, a 2.5% ophthalmic solution of povidone-iodine is desirable to use as a prophylactic agent against ophthalmia neonatorum.