Material and methods: Patients, newly diagnosed with open angle glaucoma and started Cosopt or Oftomix treatment between April 2016 and April 2017 in our clinic were enrolled in the study and were divided into two groups as Group A (Cosopt) and B (Oftomix) with respect to the drug they were given. Patients? medical records before treatment and at fourth week of treatment were retrospectively evaluated. The records were also investigated for the side effects reported by the patients.

Results: Twenty-fi ve eyes of 14 patients with similar demographical characteristics were enrolled. No statistically signifi cant differences were observed between the two groups with respect to intraocular pressure (IOP) values before and after treatment, the total decrease in IOP after treatment (p=0.226, p=0.688, p=0.226). In 33% of patients in Group A and in 50% of patients in Group B stinging of the eye was observed as a side effect. Other than that no local or systemic side effects were observed. With respect to those, there was no statistically signifi cant difference between the groups (p=0.75).

Conclusion: The short term results for effi cacy and safety of reference original drug Cosopt and its generic drug Oftomix were found to be similar. Although long term follow up is needed Oftomix can be safely used in patients for whom dorzolamide / timolol fi xed combination therapy is suitable. Keywords : Glaucoma, generic drug, original drug