Glaucoma is a leading cause of irreversible blindness worldwide. The pathogenesis of glaucoma is not entirely understood; however, major risk factors are well established and include advancing age, genetic predisposition, and increased intraocular pressure (IOP). The only known modifiable risk factor is IOP. Evidence-based treatments to lower IOP include topical ophthalmic medications, laser procedures, sustained release implants, and/or surgical interventions. The most common approach for managing glaucoma, especially for the primary care optometrist, is IOP-lowering medication.¹ Often patients with glaucoma are on multiple topical therapeutic agents to achieve optimal IOP measurements. While effective at lowering IOP, topical medications have historically contained preservatives. Preservatives are detergents used to prolong the shelf life of medications and maintain sterility; however, their presence can also have some adverse effects on the eye and cause challenges for the ocular surface.²