What is the diagnosis and treatment for allergic conjunctivitis (allergy eyes)?

Diagnosis and Treatment of Allergic Conjunctivitis

For allergic conjunctivitis, start with dual-action topical agents (olopatadine, ketotifen, epinastine, or azelastine) as first-line treatment, which provide both immediate relief and ongoing protection through combined antihistamine and mast cell stabilizer properties. 1

Clinical Diagnosis

Key diagnostic features:

• Bilateral eye involvement with itching as the predominant symptom 2
• Conjunctival injection and chemosis with tearing 2
• Often accompanies allergic rhinitis (allergic rhinoconjunctivitis) 2
• More than 75% of seasonal allergic rhinitis patients report ocular symptoms 2

Important diagnostic distinctions:

• Seasonal allergic conjunctivitis: Associated with pollen exposure (trees, grasses, weeds) 2
• Perennial allergic conjunctivitis: Year-round symptoms from indoor allergens like dust mites 2
• Vision-threatening forms requiring ophthalmology referral:
  • Vernal keratoconjunctivitis: Chronic palpebral conjunctival inflammation, predominantly in pediatric/adolescent males 2
  • Atopic keratoconjunctivitis: Associated with eczematous eyelid lesions, typically in older adults 2

Diagnostic testing when indicated:

• Allergy skin testing is highly sensitive and specific for aeroallergens 2
• Positive skin prick test identifies allergens in 82% of ocular allergy patients 2
• Diagnosis can be made clinically even with negative IgE testing if history is compelling 2

Treatment Algorithm

Step 1: Non-Pharmacological Measures (All Patients)

• Cold compresses and saline irrigation or artificial tears for mild symptoms 2, 1
• Refrigerated preservative-free artificial tears to dilute allergens and inflammatory mediators 1, 3
• Allergen avoidance: hypoallergenic bedding, frequent clothes washing, showering before bedtime 1
• Wear sunglasses as physical barrier against airborne allergens 1
• Avoid eye rubbing, which can lead to keratoconus in atopic patients 1

Step 2: First-Line Pharmacological Treatment

Dual-action topical agents (antihistamine + mast cell stabilizer):

• Olopatadine, ketotifen, epinastine, or azelastine 2, 1, 3
• Onset of action within 30 minutes, suitable for both acute and chronic treatment 2, 3
• Can be stored in refrigerator for additional cooling relief 1
• No maximum treatment duration specified, unlike corticosteroids 3
• Superior to oral antihistamines, which may worsen dry eye syndrome and impair tear film 2, 1, 3

Alternative first-line options:

• Topical antihistamines alone (emedastine, levocabastine) for acute relief 2, 3
• Combination antihistamine/vasoconstrictor (pheniramine, antazoline) works better than either agent alone 2

Step 3: Second-Line Treatment (If Inadequate Response)

Mast cell stabilizers for prophylaxis:

• Cromolyn, lodoxamide, nedocromil, or pemirolast 2, 3
• Slow onset requiring several days for optimal effect 2, 3
• Better for prophylactic or longer-term treatment than acute relief 2, 3

Topical NSAIDs:

• Ketorolac for temporary relief of ocular itching in seasonal allergic conjunctivitis 2, 3

Step 4: Third-Line Treatment (Severe Symptoms or Acute Exacerbations)

Topical corticosteroids - use with extreme caution:

• Loteprednol etabonate (Alrex) is preferred due to reduced IOP risk 2, 4
• Strictly limit to 1-2 weeks maximum 1, 3
• Requires baseline and periodic IOP measurement plus pupillary dilation to evaluate for glaucoma and cataract 1
• Vision-threatening risks: cataract formation, elevated IOP, secondary infections 2, 1, 3
• Loteprednol showed 1% IOP elevation rate vs. 6% with prednisolone acetate 4

Step 5: Refractory Cases

For severe cases unresponsive to above treatments:

• Topical cyclosporine 0.05% or tacrolimus 1, 3
• Cyclosporine 0.1% is FDA-approved for vernal keratoconjunctivitis in children and adults 1
• May allow reduced corticosteroid use 1
• For eyelid involvement (ages 2+): pimecrolimus cream 1% or tacrolimus ointment 0.03% 1

Systemic options for severe atopic/vernal keratoconjunctivitis:

• Allergen-specific immunotherapy (subcutaneous or sublingual) 1
• Rarely: montelukast, interferons, oral cyclosporine or tacrolimus 1

Systemic Treatments for Associated Rhinitis

When allergic conjunctivitis accompanies rhinitis:

• Oral antihistamines, intranasal antihistamines, oral anti-leukotriene agents, intranasal corticosteroids, and allergen immunotherapy all relieve ocular symptoms 2
• Intranasal corticosteroids, oral antihistamines, and intranasal antihistamines have similar effectiveness for eye symptoms 2
• Fluticasone furoate nasal spray significantly reduces ocular symptoms in seasonal allergic rhinitis 2

Critical Pitfalls to Avoid

• Never use punctal plugs in allergic conjunctivitis - they prevent flushing of allergens and inflammatory mediators 1, 3
• Avoid prolonged vasoconstrictor use (>10 days) - causes rebound hyperemia (conjunctivitis medicamentosa) 2, 1, 3
• Avoid oral antihistamines as primary ocular treatment - they worsen dry eye 2, 1, 3
• Never use topical antibiotics - they induce toxicity and are not indicated 1
• Monitor for keratoconus in atopic patients who rub their eyes 1

When to Refer to Ophthalmology

• Suspected vernal or atopic keratoconjunctivitis 2
• Any corneal involvement or vision changes 2
• Disease uncontrolled with topical medications and oral antihistamines 1
• Need for corticosteroid therapy beyond 1-2 weeks 1
• If symptoms fail to improve within 48 hours on dual-action drops, add brief loteprednol course with ophthalmology monitoring 1