What is the first-line treatment for acute narrow-angle glaucoma?

The first-line treatment for acute narrow-angle glaucoma is acetazolamide. This medication is a carbonic anhydrase inhibitor that reduces the production of aqueous humor, thereby lowering intraocular pressure, which is crucial in managing acute narrow-angle glaucoma.

During an acute episode, the iris is pushed forward, obstructing the outflow of aqueous humor and leading to a significant increase in intraocular pressure. Acetazolamide acts quickly to decrease this pressure and alleviate the acute symptoms.

While other medications, such as mannitol, can also be used to help lower intraocular pressure, they are often utilized in conjunction with acetazolamide. Mannitol is an osmotic agent that pulls fluid out of the eye, but acetazolamide is preferred as an initial treatment due to its mechanism of action and efficacy in preventing further complications.

Beta-blockers, such as timolol, can be part of the therapeutic regimen for chronic management of glaucoma but are not typically used as first-line treatment in an acute situation. Their onset of action is also slower compared to acetazolamide during an acute episode, making acetazolamide the optimal choice for immediate treatment.