Brinzolamide Hexal

What Is Brinzolamide Hexal and What Is It Used For?

Brinzolamide Hexal belongs to a class of medications known as carbonic anhydrase inhibitors (CAIs). These drugs work by inhibiting the enzyme carbonic anhydrase II, which is found in many tissues throughout the body, including the ciliary body of the eye. The ciliary body is responsible for producing aqueous humor, the clear fluid that fills the front portion of the eye and maintains intraocular pressure. By inhibiting carbonic anhydrase II in the ciliary processes, brinzolamide reduces the formation of bicarbonate ions, which in turn decreases sodium and water transport into the posterior chamber. This results in a measurable reduction in aqueous humor production and consequently a lowering of intraocular pressure.

Elevated intraocular pressure is the primary modifiable risk factor for the development and progression of open-angle glaucoma, the most common form of glaucoma worldwide. Glaucoma is a group of progressive optic neuropathies characterized by the gradual loss of retinal ganglion cells and their axons, leading to structural changes in the optic nerve head and corresponding visual field defects. If left untreated, glaucoma can cause irreversible blindness. The World Health Organization (WHO) estimates that glaucoma affects over 80 million people globally, making it the leading cause of irreversible blindness worldwide.

Ocular hypertension refers to a condition in which the intraocular pressure is consistently elevated above the normal range (typically above 21 mmHg) without any detectable optic nerve damage or visual field loss. While not all patients with ocular hypertension develop glaucoma, they are at significantly increased risk compared to the general population. Treatment to lower IOP in ocular hypertension is recommended when risk factors for glaucoma progression are present, such as high baseline IOP, thin central corneal thickness, older age, or a family history of glaucoma.

Brinzolamide Hexal can be prescribed as monotherapy (the sole IOP-lowering medication) when beta-blocker eye drops are contraindicated or not tolerated, or as adjunctive therapy in combination with a beta-blocker (such as timolol) or a prostaglandin analogue (such as latanoprost, travoprost, or bimatoprost) when monotherapy does not achieve adequate IOP reduction. In clinical studies, brinzolamide has demonstrated an average IOP reduction of approximately 15-20% from baseline when used as monotherapy, and provides additional IOP lowering when added to existing therapy.

What Should You Know Before Taking Brinzolamide Hexal?

Contraindications

Brinzolamide Hexal must not be used if you have a known hypersensitivity to brinzolamide, to any other sulfonamide, or to any of the excipients in the formulation. Brinzolamide is a sulfonamide derivative, and cross-sensitivity between sulfonamide antibiotics and non-antibiotic sulfonamides (including brinzolamide) has been reported, although the clinical significance of this cross-reactivity remains debated. Patients with a confirmed history of serious sulfonamide-related adverse reactions (such as Stevens-Johnson syndrome or toxic epidermal necrolysis) should avoid brinzolamide.

The medication is also contraindicated in patients with severe renal impairment (creatinine clearance below 30 ml/min). Because brinzolamide and its metabolites are primarily excreted by the kidneys, impaired renal function can lead to accumulation of the drug and its metabolites, increasing the risk of systemic side effects including metabolic acidosis. In patients with moderate renal impairment, the medication should be used with caution under close medical supervision.

Patients with hyperchloraemic metabolic acidosis should not use brinzolamide, as the drug can further exacerbate acid-base disturbances through its inhibition of carbonic anhydrase activity.

Warnings and Precautions

Brinzolamide Hexal is for ophthalmic use only and must not be taken orally or injected. Although topical ocular administration results in lower systemic absorption compared to oral carbonic anhydrase inhibitors (such as acetazolamide), some systemic absorption does occur. Therefore, systemic side effects associated with carbonic anhydrase inhibition may occur with topical use, particularly in patients who are concurrently using oral carbonic anhydrase inhibitors.

Patients with hepatic impairment should use brinzolamide with caution, as the drug has not been extensively studied in this population. Although brinzolamide undergoes relatively limited hepatic metabolism, impaired liver function may affect the overall pharmacokinetic profile of the drug.

The eye drops contain benzalkonium chloride as a preservative, which is known to cause eye irritation and may discolor soft contact lenses. Patients should remove their contact lenses before instilling the drops and wait at least 15 minutes before reinserting them. Benzalkonium chloride has also been reported to cause punctate keratopathy and/or toxic ulcerative keratopathy with prolonged use. Patients who require frequent or long-term use of preserved eye drops should have regular corneal assessments.

If patients experience any serious ocular reactions or signs of hypersensitivity (such as skin rash, swelling of the face, lips, or throat, or difficulty breathing), they should discontinue use immediately and contact their healthcare provider.

Pregnancy and Breastfeeding

There are no adequate and well-controlled studies of brinzolamide in pregnant women. Animal studies with oral brinzolamide at doses far exceeding the therapeutic ophthalmic dose have shown developmental toxicity, including reduced fetal body weights and skeletal variations. The relevance of these findings to topical ocular use in humans at therapeutic doses is uncertain due to the significantly lower systemic exposure.

Brinzolamide Hexal should only be used during pregnancy if the potential benefit justifies the potential risk to the fetus. Women of childbearing potential should discuss contraceptive options with their healthcare provider before starting treatment.

It is not known whether brinzolamide or its metabolites are excreted in human breast milk. Animal studies have shown excretion of brinzolamide in the milk of lactating rats. Given the potential for adverse effects in the nursing infant, a decision should be made whether to discontinue breastfeeding or to discontinue the drug, taking into account the importance of the drug to the mother.

How Does Brinzolamide Hexal Interact with Other Drugs?

Drug interactions with topically applied brinzolamide are generally less frequent and less severe than with systemically administered carbonic anhydrase inhibitors, due to the lower systemic exposure from ophthalmic use. However, some degree of systemic absorption does occur, and healthcare providers should be aware of potential interactions that may affect patient safety.

Major Interactions

Minor Interactions and Considerations

When using brinzolamide in combination with other topical ophthalmic medications, patients should be instructed to administer the different drops at least 5 minutes apart. This interval allows adequate time for the first drop to be absorbed and minimizes the risk of one medication washing out the other. If an ophthalmic ointment is also being used, it should be applied last, after all eye drops have been instilled.

Brinzolamide is metabolized primarily by the cytochrome P450 enzyme CYP3A4 and to a lesser extent by CYP2A6, CYP2B6, CYP2C8, and CYP3A5. The major metabolite, N-desethylbrinzolamide, also inhibits carbonic anhydrase II, although less potently than the parent drug. In vitro studies suggest that brinzolamide and N-desethylbrinzolamide do not significantly inhibit any of the major CYP450 isoenzymes, making clinically significant pharmacokinetic interactions through this pathway unlikely.

What Is the Correct Dosage of Brinzolamide Hexal?

Adults

The suspension should be shaken well before each use to ensure uniform distribution of the active ingredient. After instilling the drop, patients should gently close the eyelid and apply pressure to the nasolacrimal duct (the inner corner of the eye near the nose) for approximately 1-2 minutes. This technique, known as nasolacrimal occlusion or punctal occlusion, helps to minimize systemic absorption through the nasal mucosa and reduces the occurrence of systemic side effects such as dysgeusia (taste disturbance).

If a dose is being replaced from another antiglaucoma medication, the previous medication should be discontinued and brinzolamide started the following day. If more than one topical ophthalmic medication is being used, the medications should be administered at least 5 minutes apart.

Children

Elderly

Missed Dose

If you forget to apply a dose, apply it as soon as you remember. However, if it is almost time for your next scheduled dose, skip the missed dose and continue with your regular dosing schedule. Do not apply a double dose to make up for a forgotten dose, as excessive application may increase the risk of local irritation and systemic side effects.

Overdose

No cases of overdose with topical ophthalmic brinzolamide have been reported in the clinical literature. If excessive amounts are accidentally instilled into the eye, the eye should be rinsed with lukewarm water. In the event of accidental ingestion, treatment should be symptomatic and supportive. Electrolyte levels (particularly potassium), blood pH, and renal function should be monitored. Metabolic acidosis may develop with significant systemic exposure. Because brinzolamide binds extensively to carbonic anhydrase in red blood cells, haemodialysis is unlikely to be effective in removing the drug.

What Are the Side Effects of Brinzolamide Hexal?

Like all medicines, Brinzolamide Hexal can cause side effects, although not everybody gets them. Most side effects reported with brinzolamide are ocular (relating to the eye) and are generally mild to moderate in severity and transient in nature. Systemic side effects are less common but can occur due to absorption through the nasal mucosa and conjunctival blood vessels.

The following side effects have been reported in clinical trials and post-marketing surveillance, organized by frequency according to the MedDRA convention:

As a sulfonamide derivative, brinzolamide has the theoretical potential to cause sulfonamide-class adverse effects, although these are exceedingly rare with topical ophthalmic use. Such effects may include Stevens-Johnson syndrome, toxic epidermal necrolysis, blood dyscrasias (aplastic anaemia, agranulocytosis), hepatic necrosis, and fulminant hepatic failure. While no confirmed cases of these severe reactions have been directly attributed to topical brinzolamide, patients should be aware of this theoretical risk.

Long-term use of preserved eye drops containing benzalkonium chloride has been associated with ocular surface disease, including dry eye syndrome, punctate keratopathy, and changes to the tear film. Patients requiring long-term treatment should be regularly evaluated for signs of ocular surface damage, and preservative-free alternatives should be considered when available.

How Should You Store Brinzolamide Hexal?

Proper storage of Brinzolamide Hexal is essential to maintain the stability and efficacy of the medication. The eye drop suspension should be stored at a temperature not exceeding 25°C (77°F) in its original packaging to protect from light. Do not freeze the medication, as freezing may damage the formulation and alter the suspension properties.

Keep the bottle tightly closed when not in use to prevent contamination and evaporation. To maintain sterility, avoid touching the dropper tip to any surface, including the eye or fingers. If the dropper tip becomes contaminated, it may introduce bacteria into the eye drop solution, potentially causing ocular infections.

Once the bottle has been opened, the suspension should be used within 4 weeks. After this period, the remaining solution should be discarded, even if it appears to be unchanged, as the preservative effectiveness may diminish and microbial contamination risk increases. It is helpful to write the date of first opening on the bottle label as a reminder.

Keep all medicines out of the reach and sight of children. Do not use the medication after the expiry date stated on the bottle and outer carton. The expiry date refers to the last day of that month. Medicines should not be disposed of via wastewater or household waste. Ask your pharmacist about how to dispose of medicines no longer required in an environmentally responsible manner.

What Does Brinzolamide Hexal Contain?

The active substance in Brinzolamide Hexal is brinzolamide. Each millilitre of the suspension contains 10 mg of brinzolamide.

The other ingredients (excipients) are:

• Benzalkonium chloride (0.1 mg/ml) – a quaternary ammonium compound used as a preservative to prevent microbial growth in the multi-dose bottle. Note: benzalkonium chloride may be absorbed by soft contact lenses.
• Carbomer 974P – a polyacrylic acid polymer used as a suspending and viscosity-enhancing agent to maintain uniform drug distribution and improve ocular retention time.
• Mannitol – a sugar alcohol used as a tonicity agent to ensure the eye drops are isotonic with tear fluid, reducing ocular irritation upon instillation.
• Tyloxapol – a non-ionic surfactant used to aid in resuspension of the brinzolamide particles when the bottle is shaken.
• Sodium chloride – used to adjust tonicity.
• Disodium edetate (EDTA) – a chelating agent that enhances the antimicrobial effectiveness of benzalkonium chloride.
• Hydrochloric acid and/or sodium hydroxide – used to adjust the pH of the formulation to approximately 7.5, which is close to the natural pH of human tears.
• Purified water – the vehicle for the suspension.

The suspension has a white to off-white appearance. It is important to shake the bottle well before each use, as the active ingredient brinzolamide is present as a suspension (the drug particles are dispersed in the liquid but may settle upon standing). Failure to shake the bottle adequately may result in inconsistent dosing.

References

1. European Medicines Agency (EMA). Brinzolamide Summary of Product Characteristics (SmPC). EMA/CHMP, last updated 2024.
2. European Glaucoma Society. Terminology and Guidelines for Glaucoma, 5th Edition. Savona: PubliComm; 2020.
3. American Academy of Ophthalmology (AAO). Preferred Practice Pattern: Primary Open-Angle Glaucoma. San Francisco: AAO; 2024.
4. Iester M, et al. Brinzolamide ophthalmic suspension 1%: a review of its pharmacology and use in the treatment of open-angle glaucoma and ocular hypertension. Clinical Ophthalmology. 2008;2(3):517-523.
5. Sezgin Akçay BI, et al. The safety and efficacy of brinzolamide 1% as adjunctive therapy to travoprost 0.004% in patients with open-angle glaucoma. Journal of Ocular Pharmacology and Therapeutics. 2013;29(1):89-93.
6. Tham YC, Li X, Wong TY, et al. Global prevalence of glaucoma and projections of glaucoma burden through 2040: a systematic review and meta-analysis. Ophthalmology. 2014;121(11):2081-2090.
7. World Health Organization (WHO). World Report on Vision. Geneva: WHO; 2019.
8. DeMill DL, Adamsons IA, Bhatt HK, et al. A review of the clinical pharmacology of brinzolamide. Expert Opinion on Pharmacotherapy. 2002;3(8):1131-1138.
9. Kass MA, Heuer DK, Higginbotham EJ, et al. The Ocular Hypertension Treatment Study: a randomized trial determines that topical ocular hypotensive medication delays or prevents the onset of primary open-angle glaucoma. Archives of Ophthalmology. 2002;120(6):701-713.
10. British National Formulary (BNF). Brinzolamide. National Institute for Health and Care Excellence (NICE). Accessed February 2026.

Editorial Team

This article was written and medically reviewed by the iMedic Medical Editorial Team, comprising licensed physicians specializing in ophthalmology and clinical pharmacology.