PRODUCT DETAILS

Composition

• Active ingredients:
• Dorzolamide hydrochloride 20 mg/mL (carbonic anhydrase inhibitor)
• Timolol maleate 5 mg/mL (non-selective beta-blocker)
• Excipients (may vary by brand):
• Benzalkonium chloride (preservative in multi-dose bottles)
• Buffering agents and stabilizers
• Available also as preservative-free single-dose formulations

Indication / Use

Used to reduce elevated intraocular pressure (IOP) in:

• Open-angle glaucoma
• Ocular hypertension
• Pseudoexfoliative glaucoma (when single therapy is not enough)

It is usually prescribed when one medication alone (like a beta-blocker or carbonic anhydrase inhibitor) is insufficient.

Direction of Use

• Instill 1 drop in affected eye(s)
• Usually twice daily (morning and evening)
• If using other eye drops, wait at least 5 minutes
• Remove contact lenses before use; reinsert after ~15 minutes
• Avoid touching the dropper tip
• Use consistently at the same times daily

Side Effects

Common:

• Burning or stinging sensation
• Eye redness or irritation
• Blurred vision
• Bitter taste in mouth (from drainage into throat)
• Dry eyes or tearing

Systemic (due to timolol absorption):

• Fatigue or dizziness
• Slow heart rate
• Low blood pressure
• Shortness of breath (especially in asthma/COPD)

Serious (rare):

• Bronchospasm or breathing difficulty
• Severe allergic reaction
• Depression or mood changes
• Heart conduction problems

Warnings

• Not suitable for patients with:
• Asthma or severe COPD
• Bradycardia (slow heart rate)
• Heart block or heart failure
• Use caution in:
• Diabetes (may mask low blood sugar symptoms)
• Thyroid disease
• Kidney impairment
• May worsen breathing or heart conditions due to timolol

Interactions

May interact with:

• Oral or topical beta-blockers
• Calcium channel blockers (e.g., verapamil, diltiazem)
• Digoxin
• Antihypertensive medications
• Other glaucoma eye drops
• Insulin or antidiabetic drugs (masking hypoglycemia signs)
• CNS depressants (additive effects with fatigue/dizziness)

Caution

• Can cause temporary blurred vision → avoid driving immediately after use
• Long-term use may cause eye irritation (from preservative)
• Use carefully in elderly patients
• Do not stop abruptly without medical advice
• Watch for respiratory symptoms (cough, wheeze) or unusual fatigue
• Proper technique reduces systemic absorption (nasolacrimal occlusion can help)