Background: Prolonged usage of topical antiglaucoma medicines may result in ocular surface disease (OSD) that impairs both life quality and medication adaptation. Objective: The aim of the current study is to assess corneal epithelial thickness (CET) changes using anterior segment optical coherence tomography (AS-OCT) in patients using topical combination of beta-blockers and carbonic anhydrase inhibitors (CAIs). Patients and Methods: A total of 100 eyes of 80 participants were assessed in a randomized controlled clinical trial. Group A included 50 eyes of 40 glaucoma patients treated with combined topical Beta-blockers and CAIs with at least 3-month duration, while Group B included 50 eyes of 40 healthy participants with completely normal ophthalmological examination. All candidates received AS-OCT imaging with subsequent automated CET and total corneal thickness (CT) mapping. Results: Group A had a mean age of 49.84 (SD 4.83) years, while Group B had a mean age of 49.44 (SD 4.81) years (P=0.679). CET was considerably lower in all regions in Group A 45.94 (SD 3.96) µm compared to Group B 54.54 (SD 3.16) µm; (P-value