Glustop Eye Drop is a combination ophthalmic solution containing Dorzolamide 2% w/v and Timolol 0.5% w/v, indicated for the reduction of elevated intraocular pressure (IOP) in patients with ocular hypertension or open-angle glaucoma who are insufficiently responsive to monotherapy. Dorzolamide, a carbonic anhydrase inhibitor, decreases aqueous humor production by inhibiting the enzyme carbonic anhydrase in the ciliary processes, thereby reducing IOP. Timolol, a non-selective beta-adrenergic receptor blocker, also lowers IOP by decreasing aqueous humor formation through beta-receptor blockade in the ciliary epithelium. The combination provides an additive effect in lowering IOP more effectively than either agent alone. Glustop Eye Drop is administered topically, typically one drop twice daily, with dosage adjustments based on therapeutic response and tolerability. It is contraindicated in patients with bronchial asthma, severe chronic obstructive pulmonary disease, sinus bradycardia, second or third-degree atrioventricular block, overt cardiac failure, or hypersensitivity to any component. Common adverse reactions include ocular discomfort, burning or stinging upon instillation, blurred vision, and rarely systemic effects such as bradycardia or respiratory symptoms. Regular monitoring of intraocular pressure and cardiovascular status is recommended during therapy.