What are the recommended drops for a patient with allergic conjunctivitis?

Recommended Eye Drops for Allergic Conjunctivitis

Start with dual-action antihistamine/mast cell stabilizer drops such as olopatadine, ketotifen, epinastine, or azelastine as first-line therapy, as these provide both immediate symptom relief and ongoing protection against allergic reactions. 1

First-Line Pharmacological Treatment

Dual-action agents are the most effective first-line treatment because they combine antihistamine properties (rapid symptom relief within 30 minutes) with mast cell stabilization (prevention of future episodes). 1, 2

Specific Dual-Action Options:

• Olopatadine 0.1%: Instill 1 drop twice daily, 8-12 hours apart 2
• Ketotifen 0.025%: Instill 1 drop twice daily, 8-12 hours apart, no more than twice per day 3
• Epinastine or azelastine: Similar twice-daily dosing 1

These agents work faster than mast cell stabilizers alone and are suitable for both acute symptom control and long-term prophylaxis. 1, 2

Adjunctive Non-Pharmacological Measures

Combine drops with these supportive strategies to maximize symptom control:

• Refrigerated preservative-free artificial tears 4 times daily to dilute allergens and inflammatory mediators 1
• Cold compresses for immediate symptomatic relief 1
• Sunglasses as a physical barrier against airborne allergens 1
• Allergen avoidance: hypoallergenic bedding, eyelid cleansers, frequent clothes washing, showering before bedtime 1
• Counsel patients to avoid eye rubbing, which worsens symptoms and can lead to keratoconus in atopic patients 1

Second-Line Options (If First-Line Inadequate)

If dual-action agents don't provide adequate relief within 48 hours:

Mast Cell Stabilizers Alone:

• Cromolyn, lodoxamide, nedocromil, or pemirolast 1
• Important caveat: These require several days to achieve optimal effect and are better suited for prophylaxis than acute relief 1

Topical NSAIDs:

• Ketorolac for temporary relief of ocular itching 1
• Slower onset than dual-action agents 2

Third-Line Treatment for Severe Cases

For severe symptoms or acute exacerbations unresponsive to dual-action drops, add a brief 1-2 week course of loteprednol etabonate (low side-effect profile topical corticosteroid). 1

Critical Monitoring Requirements:

• Baseline intraocular pressure (IOP) measurement before starting 1
• Periodic IOP monitoring throughout use 1
• Pupillary dilation to evaluate for cataract formation 1
• Strictly limit corticosteroid use to 1-2 weeks maximum 1

Corticosteroid Risks:

• Elevated IOP and glaucoma 1
• Cataract formation 1
• Secondary infections 1

Fourth-Line for Refractory Cases

For severe allergic conjunctivitis (vernal or atopic keratoconjunctivitis) unresponsive to the above:

• Topical cyclosporine 0.05% at least 4 times daily 4, 1
• Topical tacrolimus 0.03% or 0.1% 4
• These agents allow for reduced corticosteroid use 4, 1
• Cyclosporine demonstrates reduction in signs and symptoms after 2 weeks 4

Special Considerations for Severe Disease:

• Supratarsal corticosteroid injection for sight-threatening atopic keratoconjunctivitis not responsive to topical therapy 4
• Systemic immunosuppression (rarely warranted): montelukast, interferons, oral cyclosporine or tacrolimus 4
• Consultation with allergist or dermatologist for disease inadequately controlled with topical medications 4

Critical Pitfalls to Avoid

• Never use punctal plugs in allergic conjunctivitis—they prevent flushing of allergens and inflammatory mediators from the ocular surface 4, 1
• Avoid chronic vasoconstrictor use (naphazoline, tetrahydrozoline)—prolonged use beyond 10 days causes rebound hyperemia (conjunctivitis medicamentosa) 1
• Avoid oral antihistamines as primary treatment—they worsen dry eye syndrome and impair the tear film's protective barrier 1
• Avoid indiscriminate topical antibiotics—they provide no benefit for allergic disease and cause toxicity 1

Duration of Treatment

• Seasonal allergic conjunctivitis: Use dual-action agents throughout the allergy season 1
• Perennial allergic conjunctivitis: Continue dual-action agents as long as allergen exposure persists, with reassessment at regular follow-up visits 1
• No maximum duration specified for dual-action agents (unlike corticosteroids or vasoconstrictors) 2

Follow-Up Strategy

• Frequency based on disease severity, etiology, and treatment response 4
• Time visits during symptomatic periods 4
• Monitor for keratoconus in patients with atopic disease, as adequate allergy control and preventing eye rubbing decrease ectasia progression 4