Products By Therapeutical Index
Ophthalmic Drugs
-
Glaucoma
I.O.P
Eye Drops
Composition
Dorzolamide (As Hydrochloride) 2%
Action
Carbonic anhydrase (CA) is an enzyme found in many tissues of the body including the eye. In
humans, carbonic anhydrase exists as a number of isoenzymes, the most active being carbonic
anhydrase II (CA-II) found primarily in red blood cells (RBCs) but also in other tissues. Inhibition of
carbonic anhydrase in the ciliary processes of the eye decreases aqueous humor secretion. The
result is a reduction in intraocular pressure (IOP).
I.O.P Ophthalmic Solution contains dorzolamide hydrochloride, a potent inhibitor of human
carbonic anhydrase II. Following topical ocular administration, I.O.P reduces elevated intraocular
pressure, whether or not associated with glaucoma. Elevated intraocular pressure is a major risk
factor in the pathogenesis of optic nerve damage and glaucomatous visual field loss. Unlike
miotics, I.O.P reduces intraocular pressure without the common adverse effects of miotics such as
night blindness, accommodative spasm, and pupillary constriction. Unlike topical beta-blockers,
I.O.P has minimal or no effect on pulse rate or blood pressure.
Topically applied beta-adrenergic blocking agents also reduce IOP by decreasing aqueous humor
secretion but by a different mechanism of action. Studies have shown that when Dorzolamide
added to a topical beta-blocker, additional reduction in IOP observed; this finding is consistent with
the reported additive effects of beta-blockers and oral carbonic anhydrase inhibitors.
