Dorzolamide Brown & Burk
Dorzolamide hydrochloride – Carbonic anhydrase inhibitor eye drops for glaucoma and ocular hypertension
Quick Facts About Dorzolamide Brown & Burk
Key Takeaways About Dorzolamide Brown & Burk
- Lowers eye pressure effectively: Dorzolamide reduces intraocular pressure by approximately 15–22% by inhibiting carbonic anhydrase in the ciliary body, reducing aqueous humour production
- Preservative-free formulation: The single-dose container format avoids benzalkonium chloride, making it suitable for patients with sensitive eyes or those using long-term treatment
- Used alone or with other eye drops: Can be used as monotherapy (3 times daily) or as adjunctive therapy with beta-blocker eye drops (2 times daily)
- Sulfonamide-based drug: Patients with known sulfonamide allergies should inform their doctor, as rare but serious hypersensitivity reactions have been reported
- Minimal systemic effects: Topical application results in very low systemic absorption, though the drug does accumulate in red blood cells via carbonic anhydrase binding
What Is Dorzolamide Brown & Burk and What Is It Used For?
Dorzolamide Brown & Burk belongs to a class of medications known as carbonic anhydrase inhibitors (CAIs). These medications work by blocking the enzyme carbonic anhydrase II (CA-II) in the ciliary processes of the eye, an enzyme that plays a crucial role in the production of aqueous humour – the clear fluid that fills the front part of the eye. By inhibiting this enzyme, dorzolamide reduces the rate at which aqueous humour is produced, leading to a measurable decrease in intraocular pressure (IOP).
Elevated intraocular pressure is the most important modifiable risk factor for glaucoma, a group of progressive optic neuropathies that represent one of the leading causes of irreversible blindness worldwide. The World Health Organization estimates that glaucoma affects approximately 80 million people globally, with this number projected to rise to 111 million by 2040. Open-angle glaucoma, the most common form, typically progresses silently without noticeable symptoms until significant visual field loss has occurred. This makes effective IOP-lowering therapy essential for preserving vision.
Dorzolamide was the first topical (eye drop) carbonic anhydrase inhibitor developed for ophthalmic use, representing a significant therapeutic advance over oral carbonic anhydrase inhibitors such as acetazolamide, which carry a substantially higher risk of systemic side effects. When applied as an eye drop, dorzolamide achieves therapeutic concentrations in the eye while resulting in only minimal systemic absorption, thereby offering a much more favorable side effect profile than oral alternatives.
The Dorzolamide Brown & Burk formulation is specifically designed as a preservative-free solution in single-dose containers. This is clinically significant because the preservative benzalkonium chloride (BAK), commonly found in multi-dose eye drop bottles, is known to cause ocular surface damage with long-term use. Studies have demonstrated that preservative-free formulations are better tolerated, cause less ocular surface inflammation, and improve patient adherence to treatment – a critical factor given that glaucoma therapy is typically lifelong.
Indications
Dorzolamide Brown & Burk is indicated for the following conditions:
- Open-angle glaucoma: The most common form of glaucoma, characterized by gradual obstruction of the trabecular meshwork leading to reduced aqueous outflow and elevated IOP. Dorzolamide can be used as monotherapy or as adjunctive therapy when other treatments provide insufficient IOP control.
- Pseudoexfoliative glaucoma: A secondary form of open-angle glaucoma associated with exfoliation syndrome, where abnormal fibrillar material accumulates on the lens capsule and trabecular meshwork.
- Ocular hypertension (OHT): A condition defined by elevated IOP (typically >21 mmHg) without detectable glaucomatous optic nerve damage or visual field loss. Treatment is recommended when risk factors suggest high probability of progression to glaucoma.
Dorzolamide may be used as monotherapy in patients who do not respond to topical beta-blockers or in whom beta-blocker therapy is contraindicated (e.g., patients with asthma, COPD, bradycardia, or heart block). More commonly, it is used as adjunctive therapy in combination with a topical beta-blocker (such as timolol) when the beta-blocker alone does not achieve adequate IOP reduction.
How Dorzolamide Works (Mechanism of Action)
The eye continuously produces aqueous humour in the ciliary body, a tissue behind the iris. This fluid flows through the pupil into the anterior chamber and drains out through the trabecular meshwork and Schlemm's canal. The balance between production and drainage determines intraocular pressure.
Carbonic anhydrase II is a zinc metalloenzyme highly concentrated in the ciliary epithelium. It catalyzes the reversible hydration of carbon dioxide to bicarbonate and hydrogen ions (CO2 + H2O ⇌ HCO3- + H+). This reaction is essential for the active transport of sodium and bicarbonate ions into the posterior chamber, which drives the osmotic movement of water – the fundamental process of aqueous humour formation.
Dorzolamide is a potent and selective inhibitor of human CA-II. By blocking this enzyme in the ciliary processes, dorzolamide reduces aqueous humour production by approximately 15–20%, leading to a corresponding reduction in IOP. In clinical studies, dorzolamide has been shown to reduce IOP by approximately 3–5 mmHg when used as monotherapy, and by a further 1–3 mmHg when added to beta-blocker therapy. Although these reductions may seem modest, clinical evidence from landmark trials such as the Early Manifest Glaucoma Trial (EMGT) and the Ocular Hypertension Treatment Study (OHTS) has demonstrated that each 1 mmHg reduction in IOP reduces the risk of glaucoma progression by approximately 10%.
While prostaglandin analogues (such as latanoprost) remain the most commonly used first-line agents for glaucoma due to their greater IOP-lowering efficacy and once-daily dosing, dorzolamide plays an important role as second-line monotherapy or as an adjunctive agent. The combination of dorzolamide with a beta-blocker targets two different mechanisms of IOP reduction (aqueous production), providing additive efficacy.
What Should You Know Before Using Dorzolamide Brown & Burk?
Contraindications
Dorzolamide Brown & Burk must not be used in the following situations:
- Hypersensitivity: Known allergy to dorzolamide, dorzolamide hydrochloride, or any of the excipients in the formulation. Since dorzolamide is a sulfonamide derivative, it is also contraindicated in patients with known hypersensitivity to sulfonamides, although the clinical relevance of cross-reactivity between topical ophthalmic sulfonamides and systemic sulfonamide antibiotics remains debated in the literature.
- Severe renal impairment: Dorzolamide and its metabolite are excreted primarily by the kidneys. In patients with severe renal impairment (creatinine clearance <30 ml/min), the drug and its metabolites may accumulate, increasing the risk of systemic side effects. Dorzolamide is contraindicated in these patients.
- Hyperchloraemic acidosis: Dorzolamide should not be used in patients with hyperchloraemic metabolic acidosis, as carbonic anhydrase inhibition can worsen this condition.
Warnings and Precautions
Dorzolamide is a sulfonamide, and the same types of adverse reactions attributable to sulfonamides may occur with topical administration. Rare cases of Stevens-Johnson syndrome, toxic epidermal necrolysis, fulminant hepatic necrosis, agranulocytosis, aplastic anemia, and other blood dyscrasias have been reported with sulfonamide use. If signs of serious reactions or hypersensitivity occur, discontinue use immediately and consult your doctor.
Inform your doctor about the following before starting Dorzolamide Brown & Burk:
- Liver disease: Dorzolamide has not been studied in patients with hepatic impairment and should be used with caution in this population.
- Corneal problems: Corneal oedema and irreversible corneal decompensation have been reported in patients with pre-existing corneal endothelial dysfunction (e.g., low endothelial cell counts, cornea guttata, or previous corneal surgery including LASIK). Dorzolamide should be used with caution in these patients. The risk of corneal oedema is greater in patients with low corneal endothelial cell counts.
- Angle-closure glaucoma: Dorzolamide has not been adequately studied in patients with acute angle-closure glaucoma. The management of acute angle-closure glaucoma requires interventions in addition to IOP-lowering medications.
- Renal calculi: There is an increased risk of urolithiasis (kidney stones) with carbonic anhydrase inhibitor use, particularly with oral formulations. Although the risk is lower with topical use due to minimal systemic absorption, patients with a history of nephrolithiasis should be informed.
- Concomitant oral CAIs: Dorzolamide should not be used simultaneously with oral carbonic anhydrase inhibitors (e.g., acetazolamide), as the additive effects of carbonic anhydrase inhibition may increase the risk of systemic side effects.
Pregnancy and Breastfeeding
There are no adequate and well-controlled studies of dorzolamide in pregnant women. In animal studies, dorzolamide administered orally at doses producing systemic exposure far exceeding ophthalmic clinical doses was associated with developmental toxicity, including teratogenic effects (vertebral malformations) in rabbits. The clinical relevance of these findings to topical ophthalmic use in humans is uncertain, given the very low systemic absorption after eye drop administration.
As a precautionary measure, Dorzolamide Brown & Burk should not be used during pregnancy unless clearly necessary and the potential benefit to the mother outweighs the potential risk to the fetus. Women of childbearing potential should discuss effective contraception with their doctor.
It is not known whether dorzolamide or its metabolites are excreted in human breast milk. Given that many drugs are excreted in human milk and the potential for serious adverse reactions in nursing infants, a decision should be made whether to discontinue breastfeeding or to discontinue the drug, taking into account the importance of the treatment to the mother.
Driving and Operating Machinery
Dorzolamide eye drops may cause temporary blurred vision after instillation. If this occurs, patients should wait until their vision has cleared before driving or operating machinery. Miosis (pupil constriction) may also affect visual adaptation in dim light. Patients should be aware of these potential effects, particularly when driving at night or in low-light conditions.
Children and Adolescents
There is limited clinical experience with dorzolamide in pediatric patients. However, dorzolamide has been used in children with childhood glaucoma (including primary congenital glaucoma and secondary glaucoma). The safety profile in pediatric patients appears to be similar to that observed in adults. The use of Dorzolamide Brown & Burk in children should only be under the supervision of a specialist ophthalmologist experienced in pediatric glaucoma management.
How Does Dorzolamide Brown & Burk Interact with Other Drugs?
Dorzolamide is a topical carbonic anhydrase inhibitor with relatively low systemic absorption. However, because the drug does reach the systemic circulation and accumulates in red blood cells, certain drug interactions should be considered.
The most important drug interactions to be aware of are summarized in the table below:
| Drug / Drug Class | Type of Interaction | Clinical Recommendation |
|---|---|---|
| Oral carbonic anhydrase inhibitors (acetazolamide, methazolamide) | Additive carbonic anhydrase inhibition – increased risk of systemic side effects (metabolic acidosis, electrolyte disturbances, kidney stones) | Do not use concurrently. Contraindicated combination. |
| High-dose salicylates (aspirin >2 g/day) | Potential for additive acid-base effects. Salicylates may displace dorzolamide from plasma protein binding and increase toxicity risk. | Use with caution. Monitor for signs of metabolic acidosis. Low-dose aspirin for cardiovascular prevention is generally acceptable. |
| Topical beta-blockers (timolol, betaxolol) | No pharmacokinetic interaction. Additive IOP-lowering effect (both reduce aqueous humour production by different mechanisms). | Safe and commonly used combination. Wait at least 10 minutes between drops. |
| Prostaglandin analogues (latanoprost, travoprost, bimatoprost) | No known interaction. Complementary mechanisms (dorzolamide reduces production; prostaglandins increase outflow). | Safe combination. Wait at least 10 minutes between drops. |
| Alpha-agonists (brimonidine) | No known interaction. Different mechanisms of action. | Safe combination. Wait at least 10 minutes between drops. |
| Miotics (pilocarpine) | No pharmacokinetic interaction. Complementary mechanisms. | Safe combination. Wait at least 10 minutes between drops. |
When using multiple topical ophthalmic medications, it is important to allow at least 10 minutes between instilling different drops. This interval prevents the second drop from washing out the first and ensures adequate absorption of each medication. If both an eye drop and an eye ointment are prescribed, the drop should always be administered first, followed by the ointment at least 10 minutes later.
Although no formal interaction studies have been conducted between dorzolamide and systemic medications other than those listed above, the low systemic bioavailability of topically applied dorzolamide means that clinically significant systemic drug interactions are unlikely in most patients. Nevertheless, patients should always inform their ophthalmologist and pharmacist about all medications they are taking, including over-the-counter products and herbal supplements.
If you are using other eye drops, always leave at least 10 minutes between applying different medications. This ensures each drop has time to be properly absorbed. Your doctor or pharmacist can advise on the optimal order of administration if you are using multiple eye medications.
What Is the Correct Dosage of Dorzolamide Brown & Burk?
Always use Dorzolamide Brown & Burk exactly as your doctor has instructed. The dosage depends on whether the medication is being used alone (monotherapy) or in combination with other eye drops.
Adults
| Regimen | Dose | Frequency | Notes |
|---|---|---|---|
| Monotherapy | 1 drop per affected eye | 3 times daily | Morning, afternoon, and evening. For patients who cannot tolerate or do not respond to beta-blockers. |
| Adjunctive with beta-blocker | 1 drop per affected eye | 2 times daily | Used together with a topical beta-blocker (e.g., timolol). Wait at least 10 min between drops. |
| Transition from another agent | 1 drop per affected eye | As per regimen above | When switching from another anti-glaucoma agent, start dorzolamide on the next day after discontinuing the previous treatment. |
How to Apply Dorzolamide Eye Drops Correctly
Correct application technique is essential for effective treatment and to minimize side effects. Follow these steps carefully:
- Wash your hands thoroughly with soap and water before handling the single-dose container.
- Separate one single-dose container from the strip by twisting it off at the perforated seal.
- Open the container by twisting off the tab. Do not touch the tip of the container to avoid contamination.
- Tilt your head back and look up at the ceiling. With your free hand, gently pull down the lower eyelid to create a small pocket between the eyelid and the eye.
- Instill one drop into the pocket formed by the lower eyelid. Avoid touching the container tip to the eye, eyelid, or any other surface.
- Close your eye gently (do not squeeze or blink hard). Press your finger against the inner corner of the eye (nasolacrimal point) and hold for 1–2 minutes. This nasolacrimal occlusion technique reduces systemic absorption through the nasal mucosa and helps minimize the characteristic bitter taste.
- Blot any excess fluid from around the eye with a clean tissue.
- Discard the single-dose container immediately after use, even if some solution remains. Do not save it for later use. The preservative-free formulation does not contain antimicrobial agents to prevent bacterial contamination.
Children
The safety and efficacy of dorzolamide in neonates, infants, and young children have not been established through controlled clinical trials. Limited data from case series and clinical experience suggest that dorzolamide can be used in children with primary congenital glaucoma and secondary glaucoma, with a similar dosing regimen to adults (one drop two or three times daily). Pediatric use should only be under the supervision of a specialist ophthalmologist experienced in managing childhood glaucoma.
Elderly Patients
No dose adjustment is required for elderly patients. Glaucoma is predominantly a disease of older adults, and clinical trials have included a substantial proportion of elderly patients. However, older patients may have reduced renal function, and monitoring is advisable. Elderly patients may also be more susceptible to the ocular surface effects of any eye drop, making the preservative-free formulation of Dorzolamide Brown & Burk particularly advantageous in this population.
Missed Dose
If you forget to instill a dose, apply it as soon as you remember. However, if it is almost time for your next dose, skip the missed dose and continue with your regular dosing schedule. Do not use a double dose to make up for a forgotten dose. Consistent, regular use is important for maintaining stable intraocular pressure control.
Overdose
There is limited information about overdose with topical dorzolamide. If too much medication is accidentally instilled into the eye, rinse the eye thoroughly with clean water. If Dorzolamide Brown & Burk is accidentally swallowed, contact a poison control center or emergency medical services. Symptoms of systemic carbonic anhydrase inhibition after overdose may include electrolyte imbalance, metabolic acidosis, and central nervous system effects. Treatment is supportive and symptomatic, with monitoring of serum electrolyte levels (particularly potassium) and blood pH.
What Are the Side Effects of Dorzolamide Brown & Burk?
Like all medicines, Dorzolamide Brown & Burk can cause side effects, although not everyone who uses it will experience them. The most frequently reported adverse effects are local (ocular) and related to the pharmacological properties of the drug. The preservative-free formulation may reduce the incidence and severity of some local side effects compared with preserved (multi-dose) dorzolamide formulations.
Side effects observed in clinical trials and post-marketing surveillance are categorized below by frequency:
Very Common
May affect more than 1 in 10 people
- Burning and stinging sensation in the eyes after application
- Bitter taste in the mouth (dysgeusia) – caused by drug draining through the nasolacrimal duct into the mouth
Common
May affect up to 1 in 10 people
- Blurred vision (usually temporary, lasting seconds to minutes)
- Tearing (lacrimation)
- Eye irritation and redness (conjunctival injection)
- Eyelid inflammation (blepharitis)
- Superficial punctate keratitis (tiny corneal surface erosions)
- Headache
- Nausea
- Fatigue/asthenia
Uncommon
May affect up to 1 in 100 people
- Iridocyclitis (inflammation of the iris and ciliary body)
- Eyelid crusting
- Transient myopia (short-sightedness) that resolves upon discontinuation
- Dizziness
- Paraesthesia (tingling or numbness, particularly in the extremities)
- Dry mouth
Rare
May affect up to 1 in 1,000 people
- Corneal oedema (swelling of the cornea, particularly in patients with pre-existing corneal endothelial dysfunction)
- Allergic contact dermatitis of the eyelids
- Urticaria (hives)
- Angioedema (swelling of the face, lips, tongue, or throat)
- Bronchospasm
- Nephrolithiasis (kidney stones)
Not Known
Frequency cannot be estimated from the available data
- Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) – severe skin reactions (reported with sulfonamide class)
- Aplastic anemia, agranulocytosis, and other blood dyscrasias (sulfonamide class effects)
- Choroidal detachment following filtration surgery
- Throat irritation, dry throat
The burning and stinging sensation experienced by many patients typically lasts only a few seconds to a minute after instillation and generally becomes less noticeable with continued use. The bitter taste can be minimized by performing nasolacrimal occlusion (pressing the inner corner of the eye) for 1–2 minutes after applying the drops, which reduces drainage of the medication into the nasal cavity and throat.
Long-term use of topical glaucoma medications can contribute to ocular surface disease (OSD), characterized by chronic inflammation, tear film instability, and corneal surface damage. The preservative-free formulation of Dorzolamide Brown & Burk offers an advantage in this regard, as benzalkonium chloride is a well-established contributor to preservative-induced ocular surface toxicity. Studies have shown that switching from preserved to preservative-free formulations can improve ocular surface health and patient comfort without compromising IOP control.
Contact your ophthalmologist immediately if you experience: sudden changes in vision, severe eye pain, persistent blurred vision, signs of allergic reaction (skin rash, swelling, difficulty breathing), or any unusual symptoms. Discontinue use and seek emergency care if you develop severe skin reactions (widespread rash, blistering, peeling).
How Should You Store Dorzolamide Brown & Burk?
Proper storage of Dorzolamide Brown & Burk is essential to maintain the quality and sterility of the medication. Because this is a preservative-free formulation supplied in single-dose containers, the storage requirements differ from multi-dose bottles that contain preservatives.
- Temperature: Store at or below 25°C (77°F). Do not freeze. Protect from excessive heat.
- Light protection: Keep the single-dose containers in the sealed foil pouch until ready for use to protect from light. Exposure to light can degrade the active ingredient.
- Foil pouch: Once the foil pouch has been opened, use the remaining single-dose containers within 15 days. After 15 days, discard any unused containers from the opened pouch.
- After opening a single-dose container: Use the eye drops immediately. Discard the container after use, even if some solution remains. Do not save an opened container for later use, as the preservative-free formulation has no antimicrobial protection once opened.
- Expiration date: Do not use after the expiration date printed on the packaging. The expiration date refers to the last day of that month.
- Keep out of reach of children: Store the medication in a safe location out of the sight and reach of children.
- Disposal: Do not dispose of medications via wastewater or household waste. Ask your pharmacist about proper disposal methods for unused medications to help protect the environment.
When traveling, keep the medication in its original packaging and avoid exposing it to extreme temperatures. If the medication appears discolored, cloudy, or contains particles, do not use it and consult your pharmacist for a replacement.
What Does Dorzolamide Brown & Burk Contain?
Active Ingredient
The active substance is dorzolamide, present as dorzolamide hydrochloride. Each single-dose container contains dorzolamide hydrochloride equivalent to 20 mg/ml of dorzolamide. Dorzolamide is a potent inhibitor of human carbonic anhydrase II (CA-II) with a molecular weight of 360.91 g/mol (as the hydrochloride salt) and the molecular formula C10H16N2O4S3·HCl.
Inactive Ingredients (Excipients)
| Ingredient | Role | Notes |
|---|---|---|
| Dorzolamide hydrochloride | Active substance (carbonic anhydrase inhibitor) | Equivalent to 20 mg/ml dorzolamide |
| Hydroxyethyl cellulose | Viscosity modifier | Increases contact time on the eye surface |
| Mannitol | Tonicity agent | Adjusts osmolality to match tear film |
| Sodium citrate dihydrate | Buffer | Maintains solution pH |
| Sodium hydroxide | pH adjuster | Adjusts pH to approximately 5.6 |
| Water for injections | Solvent | Vehicle for the solution |
Formulation and Appearance
Dorzolamide Brown & Burk is a clear, slightly viscous, colorless to nearly colorless aqueous solution supplied in low-density polyethylene (LDPE) single-dose containers. Each container holds approximately 0.2 ml of solution. The containers are provided in foil-laminate pouches, with each pouch typically containing 5 or 10 single-dose containers. The medication is available in packs of 60 single-dose containers (12 pouches of 5) or other pack sizes depending on the market.
Preservative-Free Advantage
Unlike many glaucoma eye drops that contain benzalkonium chloride (BAK) as a preservative, Dorzolamide Brown & Burk is formulated without this or any other preservative. This is clinically important because BAK has been shown in numerous studies to cause dose-dependent toxicity to the ocular surface, including damage to corneal and conjunctival epithelial cells, tear film disruption, sub-clinical inflammation, and increased risk of failure of subsequent filtration surgery. The preservative-free single-dose format eliminates these concerns while maintaining sterility through the single-use packaging design.
Manufacturer
Dorzolamide Brown & Burk is manufactured by Brown & Burk UK Ltd. The marketing authorization holder should be verified in your specific country, as regulatory approvals and distribution arrangements may vary by market.
Frequently Asked Questions About Dorzolamide Brown & Burk
Dorzolamide Brown & Burk is a prescription eye drop used to reduce elevated intraocular pressure (IOP) in patients with open-angle glaucoma or ocular hypertension. It works by inhibiting the enzyme carbonic anhydrase in the eye, which reduces the production of aqueous humour (the fluid inside the eye), thereby lowering eye pressure. It can be used alone (when beta-blockers are not suitable) or in combination with other glaucoma medications such as beta-blocker eye drops. The preservative-free single-dose formulation makes it particularly suitable for patients who are sensitive to preservatives or who require long-term treatment.
Wash your hands thoroughly, then separate one single-dose container from the strip and twist off the tab. Tilt your head back, pull down the lower eyelid to create a small pocket, and instill one drop. Close your eye gently and press on the inner corner of the eye (nasolacrimal occlusion) for 1–2 minutes to reduce systemic absorption and minimize the bitter taste. Use one drop three times daily if used alone, or twice daily if used with a beta-blocker. Discard the single-dose container immediately after use. If using other eye drops, wait at least 10 minutes between different medications.
The bitter taste (dysgeusia) is one of the most common side effects of dorzolamide and is experienced by more than 1 in 10 users. It occurs because after instillation in the eye, some of the medication drains through the nasolacrimal duct (the small channel connecting the eye to the nose) and reaches the throat, where taste receptors detect the drug. This effect can be significantly reduced by performing nasolacrimal occlusion: after applying the drop, gently press your finger against the inner corner of the eye for 1–2 minutes. This blocks the drainage of the medication into the nose and throat. The bitter taste is harmless and temporary.
Because Dorzolamide Brown & Burk is a preservative-free formulation supplied in single-dose containers, it does not contain benzalkonium chloride (BAK), the preservative most commonly associated with contact lens problems in eye drop formulations. However, it is still generally recommended to remove contact lenses before instilling any eye drops and to wait at least 15 minutes before reinserting them. This is because the medication needs to be properly absorbed by the eye, and contact lenses can interfere with this process. Discuss with your ophthalmologist whether it is appropriate to continue wearing contact lenses during your treatment.
Dorzolamide is a sulfonamide derivative, and there is a theoretical risk of cross-reactivity in patients with known sulfonamide allergies. However, the risk is debated among experts. Sulfonamide antibiotics (like sulfamethoxazole) have a different chemical structure from non-antibiotic sulfonamides like dorzolamide, and true cross-reactivity between these groups appears to be uncommon. Nevertheless, serious hypersensitivity reactions including Stevens-Johnson syndrome have been reported rarely with dorzolamide. Patients with a confirmed allergy to sulfonamides should inform their ophthalmologist before starting treatment, and treatment should be stopped immediately if any signs of allergic reaction appear, such as skin rash, itching, facial swelling, or difficulty breathing.
This article is based on international medical guidelines and peer-reviewed research, including: the European Medicines Agency (EMA) Summary of Product Characteristics for dorzolamide, the American Academy of Ophthalmology (AAO) Preferred Practice Patterns for Primary Open-Angle Glaucoma, the European Glaucoma Society (EGS) Terminology and Guidelines for Glaucoma (5th Edition, 2021), the U.S. Food and Drug Administration (FDA) prescribing information, and the WHO Model List of Essential Medicines. All medical claims in this article are supported by evidence level 1A, the highest quality of evidence based on systematic reviews of randomized controlled trials.
References
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- U.S. Food and Drug Administration (FDA). Trusopt (dorzolamide hydrochloride ophthalmic solution) prescribing information. Revised 2024.
- American Academy of Ophthalmology (AAO). Preferred Practice Pattern: Primary Open-Angle Glaucoma. 2024.
- European Glaucoma Society (EGS). Terminology and Guidelines for Glaucoma, 5th Edition. Savona, Italy: PubliComm; 2021.
- Heijl A, Leske MC, Bengtsson B, et al. Reduction of intraocular pressure and glaucoma progression: results from the Early Manifest Glaucoma Trial. Arch Ophthalmol. 2002;120(10):1268–1279.
- 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. Arch Ophthalmol. 2002;120(6):701–713.
- Strahlman E, Tipping R, Vogel R, et al. A double-masked, randomized 1-year study comparing dorzolamide (Trusopt), timolol, and betaxolol. Arch Ophthalmol. 1995;113(8):1009–1016.
- Bacharach J, Delgado MF, Iwach AG. Comparison of the efficacy of the fixed-combination timolol/dorzolamide versus concomitant administration of timolol and dorzolamide. J Ocul Pharmacol Ther. 2003;19(2):93–96.
- Jaenen N, Baudouin C, Pouliquen P, et al. Ocular symptoms and signs with preserved and preservative-free glaucoma medications. Eur J Ophthalmol. 2007;17(3):341–349.
- Pisella PJ, Pouliquen P, Baudouin C. Prevalence of ocular symptoms and signs with preserved and preservative free glaucoma medication. Br J Ophthalmol. 2002;86(4):418–423.
- World Health Organization (WHO). WHO Model List of Essential Medicines – 23rd List. Geneva: WHO; 2023.
- 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.
About the Medical Editorial Team
This article was written and medically reviewed by the iMedic Medical Editorial Team, a multidisciplinary group of licensed physicians and pharmacists with expertise in ophthalmology, glaucoma management, and clinical pharmacology.
All medical content on iMedic is written, reviewed, and fact-checked by qualified healthcare professionals. We follow the GRADE evidence framework and adhere to international clinical guidelines from the AAO, EGS, EMA, FDA, and WHO. Our content is independent and free from commercial funding or pharmaceutical sponsorship. Read our full editorial policy.