Glaucoma affects 3 million Americans — half undiagnosed. This 2026 guide covers all eye drop classes, latanoprost reducing IOP 25–35% once daily (first-line), timolol absolute asthma contraindication, why iris darkening is permanent, the nasolacrimal occlusion technique, a 9-drug comparison table, and Rocklatan achieving 40% IOP reduction — the highest of any single product.