Comparison of Effects of Preserved and Preservative Free Anti-Glaucoma Drugs in Causing Dry Eyes

Objective: The aim of this study was to assess the potential impact of antiglaucoma medication preservatives on ocular surface health and the subsequent development of dry eye symptoms. Methods: A non-randomized controlled trial study was conducted from March 2023 to June 2023.The study enrolled 32 patients, with 16 participants in each group. Patients meeting the inclusion criteria, including confirmed diagnosis of glaucoma and stable ocular health, were allocated to Group A(preserved medication) or Group B(preservative-free medication).Tear Film Break-Up Time(TBUT) and Schirmer's test were employed as objective indicators of tear film stability and tear production respectively. Measurements were recorded at baseline and after a 3-month duration of medication use. Results: At 1st visit, mean TBUT was 10.87 sec and mean Schirmer's test was 13.75 mm in group A while in group B it was 11.25 sec and 14.56 mm respectively. After 3 months of medication use, mean TBUT and mean Schirmer’s was 9.62 sec and 11.81 mm respectively in group A while in group B it was 10.18 sec and 13.18 mm respectively. The results showed that initial ocular status was similar in both groups however the decrease in values showed ocular surface deterioration. Notably group A demonstrated a more substantial decline in tear production compared to group B. Conclusion: This study underscores the importance of both preserved and preservative-free anti-glaucoma medications. Although both may potentially exacerbate dry eye symptoms to a greater extent, preservative-free anti-glaucoma may offer benefits in maintaining ocular surface health with long-term use.