What is the treatment for allergic conjunctivitis?

Treatment for Allergic Conjunctivitis

Dual-action topical agents (olopatadine, ketotifen, epinastine, or azelastine) are the most effective first-line treatment for allergic conjunctivitis, providing both rapid symptom relief and ongoing protection. 1

First-Line Treatment Approach

Pharmacological therapy:

• Dual-action agents (antihistamine + mast cell stabilizer) should be initiated immediately as they provide onset of action within 30 minutes and maintain efficacy for at least 8 hours 2
• Specific agents include olopatadine, ketotifen, epinastine, and azelastine—all are suitable for both acute symptom relief and longer-term prophylactic treatment 1
• These agents can be stored in the refrigerator for additional cooling relief upon instillation 1
• Unlike corticosteroids or vasoconstrictors, dual-action agents have no specified maximum treatment duration, supporting extended use without safety concerns 2

Non-pharmacological measures (implement concurrently):

• Cold compresses and irrigation with saline solution or refrigerated preservative-free artificial tears to dilute allergens and inflammatory mediators 1, 2
• Wear sunglasses as a physical barrier against airborne allergens 1
• Implement allergen avoidance strategies including hypoallergenic bedding, frequent clothes washing, and bathing/showering before bedtime 1
• Counsel patients to avoid eye rubbing, which can worsen symptoms and potentially lead to keratoconus, especially in atopic patients 1, 3

Second-Line Treatment Options

If symptoms remain inadequately controlled after 1-2 weeks of dual-action agents:

Mast cell stabilizers alone:

• Consider cromolyn, lodoxamide, nedocromil, or pemirolast for prophylactic or longer-term treatment 1
• These agents have slower onset of action (several days) but are effective for prevention 2

Topical NSAIDs:

• Ketorolac provides temporary relief of ocular itching caused by seasonal allergic conjunctivitis 1
• However, research suggests ketorolac is inferior to dual-action agents like olopatadine and emedastine 4

Third-Line Treatment for Severe Cases

Brief course of topical corticosteroids:

• Reserve loteprednol etabonate for severe symptoms or acute exacerbations only 1, 5
• Limit duration to 1-2 weeks maximum 1, 2
• Loteprednol etabonate has a low side effect profile with only 1% incidence of clinically significant IOP increases (≥10 mmHg), compared to 6% with prednisolone acetate 1% 5
• Critical monitoring requirements: Obtain baseline and periodic intraocular pressure measurements and perform pupillary dilation to evaluate for glaucoma and cataract formation 1, 3

Fourth-Line Treatment for Refractory Cases

Topical immunomodulators:

• Topical cyclosporine 0.05% or tacrolimus for severe cases unresponsive to above treatments 1, 3
• Cyclosporine 0.1% is FDA approved for vernal keratoconjunctivitis in children and adults 1
• These agents may allow for reduced use of topical steroids in vernal keratoconjunctivitis or atopic conjunctivitis 1

Allergen-specific immunotherapy:

• Consider subcutaneous or sublingual immunotherapy for patients with inadequate control despite topical medications 3

Critical Pitfalls to Avoid

Avoid chronic vasoconstrictor use:

• Over-the-counter antihistamine/vasoconstrictor combinations cause rebound vasodilation (conjunctivitis medicamentosa) with prolonged use 1, 2

Avoid oral antihistamines as primary treatment:

• Oral antihistamines may worsen dry eye syndrome and impair the tear film's protective barrier 1, 2, 3
• While second-generation oral antihistamines avoid sedation, they are inferior to topical agents for isolated ocular symptoms 4

Avoid punctal plugs:

• Punctal plugs prevent flushing of allergens and inflammatory mediators from the ocular surface 1, 3

Avoid indiscriminate antibiotic use:

• Topical antibiotics can induce toxicity and are not indicated for allergic conjunctivitis 1

Special Considerations

For vernal or atopic keratoconjunctivitis:

• Follow the same stepwise approach but anticipate need for earlier escalation to immunomodulators 3
• Supratarsal injection of corticosteroid may be considered for severe sight-threatening cases unresponsive to topical therapy 3

When to refer:

• Consultation with an allergist or ophthalmologist is beneficial for severe or refractory cases 1, 3