Provided herein are methods of treating glaucoma in a patient, comprising: obtaining a biological sample from the patient; testing the biological sample for presence of a mutation in Kir6.2 protein or KCNJ11 gene; and provided that the biological sample tests positive for the presence of a mutation in Kir6.2 protein or KCNJ11 gene, administering to the patient a therapeutically effective amount of a composition comprising tolbutamide or a physiologically equivalent salt or solvate thereof and a pharmaceutically acceptable carrier. Also provided herein are methods of maintaining and/or improving eye health in a subject, comprising: administering to the patient a therapeutically effective amount of a composition comprising tolbutamide or a physiologically equivalent salt or solvate thereof, and a pharmaceutically acceptable carrier.