Carbonic anhydrase (CA) is an enzyme found in many tissues of the body including the eye. It catalyses the reversible reaction involving the hydration of carbon dioxide and the dehydration of carbonic acid. It exists as a number of isoenzymes, the most active being carbonic anhydrase II (CA-II), found primarily in red blood cells, but also in other tissues. 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 fuid transport.

Following topical ocular administration, brinzolamide inhibits aqueous humor formation and reduces elevated intraocular pressure. Elevated intraocular pressure is a major risk factor in the pathogenesis of optic nerve damage and glaucomatous visual feld loss.

Brinzolamide Ophthalmic Suspension is indicated as monotherapy, or as adjunctive therapy to beta-blockers in the treatment of elevated intraocular pressure in ocular hypertension, or open-angle glaucoma.

The recommended dose is one drops of this eye drop in the conjunctival sac of the affected eye(s) twice daily. Some patients may have a better response with one drop three times a day. Shake well before use.

It is contraindicated in patients who are hypersensitive to any component of this product.

Reported side effects are blurred vision and bitter, sour or unusual taste. Other side effects are blepharitis, dermatitis, dry eye, foreign body sensation, headache, hyperemia, ocular discharge, ocular discomfort, ocular keratitis, ocular pain, ocular pruritus and rhinitis.

Overdose Effects

Although no human data are available, electrolyte imbalance, development of an acidosis state, and possible nervous system effects may occur following oral administration of an overdose. Serum electrolyte levels (particularly potassium) and blood pH levels should be monitored.

• Brinzolamide ophthalmic suspension and its metabolite are excreted predominantly by the kidney. So, it is not recommended in severe renal impaired patients.
• Brinzolamide ophthalmic suspension has not been studied in patients with hepatic impairment and should be used with caution in such patients.
• The concomitant administration of Brinzolamide ophthalmic suspension and oral carbonic anhydrase inhibitor is not recommended due to no additional benefits.
• If hypersensitivity reaction occurs after instillation patients should be advised to discontinue the use of Brinzolamide and consult with physicians.

Pregnancy & Lactation

Pregnancy category C. There are no adequate and well-controlled studies in pregnant women. Brinzolamide 1% ophthalmic suspension should be used during pregnancy only if the benefit justifies the potential risk to the fetus.

Use in lactation: It is not known whether Brinzolamide 1% ophthalmic suspension is excreted in human milk. So, lactating mother should discontinue nursing or to discontinue the drug, depending upon the importance of the drug to the mother.