How does Clonidine lower intraocular pressure (IOP)?

Clonidine lowers intraocular pressure primarily by acting as an alpha-2 adrenergic agonist. This action reduces the production of aqueous humor, but more importantly, it enhances the outflow of aqueous humor through the uveoscleral pathway. By stimulating alpha-2 adrenergic receptors in the ocular tissues, clonidine can effectively lead to increased drainage of fluid from the interior of the eye, thereby lowering intraocular pressure.

The uveoscleral pathway is a significant route for aqueous humor outflow and is less emphasized in other mechanisms. By promoting drainage through this pathway, clonidine can contribute to the reduction of IOP in patients with conditions like glaucoma.

This is why the mechanism involving the increase of outflow via the uveoscleral pathway is the correct answer. Other options do not reflect the primary mechanism of action for clonidine in the context of its effect on intraocular pressure.