What is the dosage and treatment protocol for Adopt (brinzolamide) in managing glaucoma?

Brinzolamide (Azopt) Dosing and Treatment Protocol for Glaucoma

Brinzolamide 1% ophthalmic suspension should be dosed as one drop in the affected eye(s) three times daily, with the bottle shaken well before each use. 1

Standard Dosing Regimen

• The FDA-approved dosing is one drop three times daily in the affected eye(s), which is the recommended starting regimen. 1

• Twice-daily dosing is also clinically effective and produces statistically equivalent IOP reductions compared to three-times-daily dosing, with mean IOP reductions ranging from -3.8 to -5.7 mmHg for twice-daily versus -4.2 to -5.6 mmHg for three-times-daily administration. 2, 3

• For patients prioritizing convenience and adherence, twice-daily dosing is a reasonable alternative that maintains therapeutic efficacy while potentially improving compliance. 3

Combination Therapy Protocol

• When using brinzolamide with other topical ophthalmic medications, administer drops at least 10 minutes apart to prevent washout and maintain efficacy. 1

• Brinzolamide can be combined with beta-blockers (such as timolol) or prostaglandin analogs to achieve additive IOP-lowering effects when monotherapy is insufficient. 1, 4, 5

• The combination with prostaglandin analogs is particularly rational because prostaglandins increase carbonic anhydrase activity in ciliary epithelium as a secondary effect, which brinzolamide can counteract while providing additional IOP reduction. 4

Expected Therapeutic Response

• Clinically relevant IOP reductions (≥5 mmHg reduction or achieving IOP ≤21 mmHg) occur in 75.7% of patients on twice-daily dosing and 80.1% on three-times-daily dosing. 2

• The IOP-lowering effect ranges from 13.5% to 20.9% reduction from baseline, with mean absolute reductions of 3.5 to 5.2 mmHg depending on dosing frequency. 5

• Check IOP response within 2-4 weeks of initiation to confirm adequate pressure reduction, following standard glaucoma management principles. 6

Clinical Context and Positioning

• Brinzolamide is indicated for elevated IOP in patients with ocular hypertension or open-angle glaucoma as either monotherapy or adjunctive therapy. 1

• While prostaglandin analogs provide superior IOP-lowering as first-line monotherapy, brinzolamide serves as an effective second-line option or adjunctive agent. 7

• Brinzolamide is particularly valuable in patients who cannot tolerate or have contraindications to beta-blockers, as it avoids systemic cardiovascular and pulmonary effects. 8

Safety Considerations and Contraindications

• Brinzolamide is contraindicated in patients with sulfonamide hypersensitivity, as it is a sulfonamide that absorbs systemically and can cause severe reactions including Stevens-Johnson syndrome, toxic epidermal necrolysis, and blood dyscrasias. 1

• Do not use in patients with severe renal impairment (creatinine clearance <30 mL/min), as brinzolamide and its metabolites are excreted predominantly by the kidney. 1

• Exercise caution in patients with low corneal endothelial cell counts due to increased risk of corneal edema, as carbonic anhydrase activity is present in corneal endothelium. 1

• Brinzolamide has not been studied in acute angle-closure glaucoma and requires additional therapeutic interventions beyond IOP-lowering agents in this setting. 1

Tolerability Profile

• Brinzolamide causes significantly less ocular discomfort (burning/stinging) on instillation compared to dorzolamide (1.8-3.0% versus 16.4%), making it better tolerated while maintaining equivalent efficacy. 2

• The most common adverse events are blurred vision (3-8%), ocular discomfort (1.8-5.9%), and eye pain (0.7-4.0%), which are generally mild, transient, and nonserious. 4, 2

• Unlike oral carbonic anhydrase inhibitors, topical brinzolamide does not produce clinically significant acid-base disturbances, electrolyte abnormalities, or severe systemic adverse effects. 8, 3

Contact Lens Considerations

• Remove contact lenses before instillation, as the preservative benzalkonium chloride can be absorbed by soft lenses; lenses may be reinserted 15 minutes after administration. 1

Contamination Prevention

• Avoid contact between the dropper tip and the eye or surrounding structures to prevent bacterial contamination, which can cause serious ocular infections and vision loss. 1