Effect of benzalkonium chloride–preserved timolol maleate on dry eye disease in a black African population, southwestern Nigeria

Objective: Benzalkonium chloride, a commonly used preservative in many ophthalmic preparations, has been postulated as a cause of ocular surface toxicity, resulting in dry eye disease in patients on long-term treatment with topical medications. This study aims to determine the effect of benzalkonium chloride–preserved timolol maleate on dry eye disease in an African population. Materials and Methods: Information was retrieved from the data generated at a cross-sectional study on the prevalence of dry eye disease conducted in a randomly selected local government area, southwestern Nigeria, and analysis was conducted on participants with glaucoma and using benzalkonium chloride–preserved timolol maleate (cases), and age- and sex-matched controls. Results: One hundred and seventy-four participants were included in this study with a mean age of 65.05 ± 11.65 years. There was no significant association (P > 0.05) between the use of benzalkonium chloride–preserved timolol maleate and tear-film break-up time, Schirmer 1 test, fluorescein staining score, and overall diagnosis of dry eye disease in the patients. Conclusion: Benzalkonium chloride–preserved timolol maleate did not contribute significantly to dry eye disease in the studied population.