Which of the following drugs decrease intraocular pressure by increasing uveoscleral outflow?

Brimonidine is a selective alpha-2 adrenergic agonist that effectively decreases intraocular pressure (IOP) primarily by increasing uveoscleral outflow. This drug works by enhancing the drainage of aqueous humor through the uveoscleral pathway, which helps to reduce the overall IOP in conditions such as glaucoma.

The mechanism of action of brimonidine is crucial in therapeutic strategies for managing ocular hypertension. By activating alpha-2 receptors, brimonidine inhibits the release of norepinephrine, leading to decreased aqueous humor production and increased outflow, thus lowering IOP. This dual action provides a beneficial effect in managing glaucoma.

Other choices, while they may also play roles in lowering intraocular pressure, do not primarily act through this specific pathway. Pilocarpine, for example, is a cholinergic agonist that works by increasing trabecular outflow, whereas timolol, a non-selective beta-blocker, lowers IOP mainly by decreasing aqueous humor production. Dorzolamide, as a carbonic anhydrase inhibitor, also primarily reduces the secretion of aqueous humor rather than directly increasing uveoscleral outflow. Thus, brimonidine stands out as the correct choice for its specific