Materials and Methods: 43 glaucoma patients (43 right eyes) who were switched from BAC-containing latanoprost to BAC-free formulations between June 2022 and February 2025 were retrospectively analyzed. At the time of switching to a BAC-free formulation, IOP and TBUT were recorded and compared with the follow up assessments conducted and 1st, 6th and 12 months.

Results: After the treatment switch, a significant difference was observed in IOP between 1st and 6th months. However, no significant difference in IOP changes was observed between the treatment switch-first month and 6th and 12th month (p>0.05). Additionally, a statistically significant difference was noted in the measurements for TBUT (treatment switch-1st month, 1st month-6th month and 6th month-12th month) (p<0.001).

Conclusion: In this study, switching from BAC-containing to BAC-free latanoprost was associated with no clinically significant difference in IOP, suggesting similar effectiveness. Additionally, the transition to BAC-free latanoprost was linked to an improvement in TBUT, indicating a potential benefit for tear film stability. Although this study did not include other dry eye parameters or patientreported outcomes, the observed TBUT improvement may contribute to better ocular comfort and treatment adherence. To our knowledge, this is the first study in Turkey to evaluate the clinical effects of BAC-free latanoprost on IOP control and tear film stability. Keywords : Benzalkonium Chloride, Glaucoma, Intraocular pressure, Topical latanoprost treatment