DORZOLAMIDE HYDROCHLORIDE TIMOLOL MALEATE

12.1 Mechanism of Action Dorzolamide hydrochloride and timolol maleate ophthalmic solution is comprised of two components: Dorzolamide hydrochloride and timolol maleate. Each of these two components decreases elevated intraocular pressure, whether or not associated with glaucoma, by reducing aqueous humor secretion. Elevated intraocular pressure is a major risk factor in the pathogenesis of optic nerve damage and glaucomatous visual field loss. The higher the level of intraocular pressure, the greater the likelihood of glaucomatous field loss and optic nerve damage. Dorzolamide hydrochloride is an inhibitor of human carbonic anhydrase II. Inhibition of carbonic anhydrase in the ciliary processes of the eye decreases aqueous humor secretion, presumably by slowing the formation of bicarbonate ions with subsequent reduction in sodium and fluid transport. Timolol maleate is a beta1 and beta2 (non-selective) adrenergic receptor blocking agent that does not have significant intrinsic sympath

Contraindications

• • 4 CONTRAINDICATIONS Dorzolamide hydrochloride and timolol maleate ophthalmic solution is contraindicated in patients with: Bronchial asthma or a history of bronchial asthma
• • severe chronic obstructive pulmonary disease. ( 4.1 ) Sinus bradycardia
• • second or third degree atrioventricular block
• • overt cardiac failure
• • cardiogenic shock. ( 4.2 ) Hypersensitivity to any component of this product. ( 4.3