Background: Glaucoma is a chronic, progressive disease of visual loss and blindness that is often managed pharmacologically. The objective of this study was to evaluate glaucoma drug prescribing trends by ophthalmologists in the United States from 2018 to 2022. Methods: Data on ophthalmologist prescribers were abstracted from Medicare Part D Prescriber Public Use Files to identify the total number of claims for each drug. Drugs were classified by type (generic or brand-name) and by drug class (carbonic anhydrase inhibitors, alpha-2 agonists, beta-blockers, prostaglandin analogs, rho kinase inhibitors, parasympathomimetic drugs, and mixed-mechanism drugs). The types of drugs prescribed were compared longitudinally. Results: Forty glaucoma drugs were prescribed under Medicare Part D from July 1st, 2018, to June 30th, 2022. A dip in total claims and claims by drug class was observed from 2018-2019 to 2019-2020. This was followed by increases to the greater number of claims in 2021-2022. Prostaglandin analogues were the most frequently prescribed class, and the most commonly prescribed drugs were latanoprost, timolol, and the dorzolamide/timolol combination. The majority of claims consisted of generics, and this value increased longitudinally as well. The most rapidly growing class prescribed by physicians was rho kinase inhibitors. Conclusion: Longitudinal differences in Medicare Part D glaucoma drug claims may reflect changing practice patterns and preferences among providers. An increasing number of claims annually, with the exception of the COVID-19 pandemic onset, reflects the growing prevalence of glaucoma. The utilization of new glaucoma agents, such as rho kinase inhibitors, is rapidly increasing as a new therapeutic option.