Dorzolamide is a carbonic anhydrase inhibitor. It is an anti-glaucoma agent, and acts by decreasing the production of aqueous humour. Dorzolamide hydrochloride is used to lower increased intraocular pressure in open-angle glaucoma and ocular hypertension. Dorzolamide does not appear to produce the acid-base or electrolyte disturbances and severe systemic adverse events associated with oral CA inhibitors, and unlike beta-adrenergic antagonists, it is not contraindicated in patients with asthma, reactive airways disease or heart disease. Dorzolamide and timolol ophthalmic (eye) drops is used to treat increased pressure in the eye caused by open-angle glaucoma or a condition called hypertension of the eye. Both eye conditions are caused by high pressure in your eye and can lead to pain from pressure in your eye and then can eventually harm your vision.