What are the recommended eye drops for allergic conjunctivitis?

Recommended Eye Drops for Allergic Conjunctivitis

For allergic conjunctivitis, dual-action agents that combine antihistamine and mast cell stabilizing properties are the most effective first-line treatment, with options like olopatadine, ketotifen, azelastine, and epinastine showing superior efficacy compared to single-action medications. 1

Treatment Algorithm Based on Severity

Mild Allergic Conjunctivitis

1. First-line therapy:

   • Dual-action antihistamine/mast cell stabilizers
     • Ketotifen 0.025% (twice daily) 2, 3
     • Olopatadine (once or twice daily depending on concentration)
     • Epinastine (twice daily)
     • Azelastine (twice daily)

2. Alternative options:

   • Over-the-counter topical antihistamine/vasoconstrictor combinations
   • Second-generation topical H1-receptor antagonists 1

Moderate Allergic Conjunctivitis

1. First-line therapy: Same dual-action agents as above
2. Adjunctive therapy:
   • Refrigerated preservative-free artificial tears (helps dilute allergens and inflammatory mediators) 1
   • Cold compresses

Severe or Persistent Allergic Conjunctivitis

1. First-line: Dual-action agents as above
2. Add if inadequate control:
   • Brief course (1-2 weeks) of topical corticosteroids with low side-effect profile 1
   • Consider topical cyclosporine or tacrolimus for severe cases 1

Specific Medication Details

Dual-Action Agents (Most Effective)

• Olopatadine: Available in different concentrations (0.1%, 0.2%, 0.77%)

  • Higher concentration (0.77%) shows longer duration and better efficacy for ocular itch 4
  • Once-daily dosing for higher concentrations

• Ketotifen 0.025%:

  • Dosing: 1 drop in affected eye(s) twice daily, every 8-12 hours 2
  • Onset of action within 20 minutes, duration 8-13 hours 5
  • Shows efficacy in reducing both signs and symptoms of allergic conjunctivitis 3

• Azelastine and Epinastine:

  • Twice-daily dosing
  • Epinastine 0.05% has shown superior or equal efficacy to olopatadine 0.1% 4

Mast Cell Stabilizers

• Cromolyn sodium 4%:
  • Dosing: 1-2 drops in each eye 4-6 times daily at regular intervals 6
  • Symptomatic response may take several days, with up to six weeks sometimes required 6
  • Better for preventive use rather than acute symptom relief

Important Clinical Considerations

• Medication storage: Store topical medications in the refrigerator when possible - the cooling sensation provides additional symptomatic relief 1

• Caution with vasoconstrictors: Chronic use can lead to rebound vasodilation once discontinued 1

• Avoid punctal plugs: They prevent flushing of allergens and inflammatory mediators from the ocular surface 1

• Monitor for complications: If corticosteroids are used, baseline and periodic IOP measurements and pupillary dilation should be performed to evaluate for glaucoma and cataract 1

• Oral antihistamines: May induce or worsen dry eye syndrome and impair the tear film's protective barrier 1

• Non-pharmacological measures:

  • Wear sunglasses as a barrier to airborne allergens
  • Use cold compresses
  • Avoid eye rubbing
  • Use hypoallergenic bedding
  • Frequent clothes washing
  • Bathing/showering before bedtime 1

For patients with allergic conjunctivitis that cannot be adequately controlled with topical medications, consultation with an allergist or dermatologist may be helpful to consider allergen-specific immunotherapy 1.