Overview
11 DESCRIPTION Dorzolamide hydrochloride and timolol maleate ophthalmic solution, USP is the combination of a topical carbonic anhydrase inhibitor and a topical beta-adrenergic receptor blocking agent. Dorzolamide hydrochloride is described chemically as: (4S-trans)-4-(ethylamino)-5,6-dihydro-6-methyl-4H-thieno[2,3-b]thiopyran-2-sulfonamide 7,7-dioxide monohydrochloride.
Mechanism of Action
12 CLINICAL PHARMACOLOGY 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.
Indications
- 1 INDICATIONS & USAGE Dorzolamide hydrochloride and timolol maleate ophthalmic solution is indicated for the reduction of elevated intraocular pressure (IOP) in patients with open-angle glaucoma or ocular hypertension who are insufficiently responsive to beta-blockers (failed to achieve target IOP determined after multiple measurements over time). The IOP-lowering of dorzolamide hydrochloride and timolol maleate ophthalmic solution administered twice a day was slightly less than that seen with the concomitant administration of 0.
Common Doses
- Refer to label
Dosage
2 DOSAGE & ADMINISTRATION The dose is one drop of dorzolamide hydrochloride and timolol maleate ophthalmic solution in the affected eye(s) two times daily. If more than one topical ophthalmic drug is being used, the drugs should be administered at least five minutes apart [see Drug Interactions (7.3)]. The dose is one drop of dorzolamide hydrochloride and timolol maleate ophthalmic solution in the affected eye(s) two times daily. (2)
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, 5.3) 4.1 Asthma, COPD Dorzolamide hydrochloride and timolol maleate ophthalmic solution is contraindicated in patients with bronchial asthma, a history of bronchial asthma, or severe chronic obstructive...
Side Effects
- 6 ADVERSE REACTIONS The most frequently reported adverse reactions were taste perversion (bitter, sour, or unusual taste) or ocular burning and/or stinging in up to 30% of patients. Conjunctival hyperemia, blurred vision, superficial punctate keratitis or eye itching were reported between 5 to 15% of patients. (6) To report SUSPECTED ADVERSE REACTIONS, contact Indoco Remedies Limited at +1-855-642-2594 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch . 6.
Interactions
- 7 DRUG INTERACTIONS Potential additive effect of oral carbonic anhydrase inhibitor with dorzolamide hydrochloride and timolol maleate ophthalmic solution. (7.1) Potential acid-base and electrolyte disturbances. (7.2) Concomitant use with systemic beta-blockers may potentiate systemic beta blockade. (7.3) Oral or intravenous calcium antagonists may cause atrioventricular conduction disturbances, left ventricular failure, and hypotension. (7.4) Catecholamine-depleting drugs may have additive effects and produce hypotension and/or marked bradycardia. (7.