Description
Brinzolamide is a highly specific, non-competitive, reversible carbonic anhydrase inhibitor. Carbonic anhydrase is an enzyme found in many tissues of the body including the eye. It catalyzes the reversible reaction involving the hydration of carbon dioxide and the dehydration of carbonic acid. In humans, carbonic anhydrase exists as a number of isoenzymes, the most active being carbonic anhydrase II. Following topical ocular administration, brinzolamide inhibits carbonic anhydrase II, an enzyme that is responsible for the movement of sodium and fluid transport in the eye. This inhibition leads to a decrease in aqueous humor secretion, probably by slowing the formation of bicarbonate ions and results in a reduction in intraocular pressure.
Brinzolamide is absorbed systemically following topical ocular administration. Since it has a high affinity for carbonic anhydrase II, brinzolamide binds extensively to red blood cells, where carbonic anhydrase II is primarily found. As sufficient carbonic anhydrase II activity remains, adverse effects resulting from the systemic inhibition of CA by brinzolamide are not observed.