Benclonidine is primarily used in the field of ophthalmology as a treatment for glaucoma and ocular hypertension. It works by reducing the production of aqueous humor and increasing its outflow, thereby lowering intraocular pressure. This helps in preventing damage to the optic nerve and preserving vision. Additionally, Benclonidine is sometimes employed in diagnostic procedures to assess the presence of Horner's syndrome, as it can help differentiate between preganglionic and postganglionic lesions. Its vasoconstrictive properties also make it useful in managing redness and irritation in the eyes, providing symptomatic relief in conditions like allergic conjunctivitis. Use under medical supervision to ensure appropriate treatment and minimize potential side effects.