Prescription trends for preservative free glaucoma medication in a public health system

Purpose To analyze the prescribing trends over a 7-years period, between 2013 and 2020, in a tertiary hospital (Hospital Clinico San Carlos, Madrid, Spain) and its health area. Material and methods A retrospective study on the data collected from the information systems, "farm@web" and "Farmadrid", of glaucoma prescriptions in the framework of a public health system (Spanish National Health System) during the last seven years. Results Prostaglandin analogues were the most commonly used drugs in monotherapy during the study period (range: 36.82% - 47.07%). Fixed combinations of topical hypotensives had an upward trend since 2013 (range: 39.99% - 54.21%), becoming the most dispensed drugs in 2020 (48.99%). Preservative-free eye drops (lacking benzalkonium chloride, BAK) have displaced preservative containing topical treatments in all pharmacological groups. In 2013, BAK-preserved eye drops accounted for 91.1% of the total prescriptions, however in 2020 they only accounted for 34.2% of total prescriptions. Conclusions The results of the present study highlight the current trend to avoid BAK-preserved eye drops for the treatment of glaucoma.