Which drug is commonly used topically to treat glaucoma?

Timolol is a non-selective beta-adrenergic antagonist that is commonly used in topical form to treat glaucoma. Its mechanism of action involves reducing intraocular pressure by decreasing the production of aqueous humor within the eye. This is crucial for patients with glaucoma, as elevated intraocular pressure can lead to damage of the optic nerve and potential vision loss.

In clinical practice, timolol is often favored because it is effective, has a well-established safety profile, and is convenient for patients as it can be administered as eye drops. The topical formulation allows for localized treatment with minimized systemic effects, which is particularly important for managing chronic conditions like glaucoma.

Other options like esmolol are primarily used in acute settings for cardiac arrhythmias or hypertension and are not suitable for glaucoma treatment. Silodosin is focused on treating benign prostatic hyperplasia and does not affect intraocular pressure, while yohimbine is mainly used for erectile dysfunction and does not have any role in managing glaucoma. Thus, timolol stands out as the correct and relevant therapeutic agent for the treatment of glaucoma when applied topically.