What is the treatment for allergic conjunctivitis?

Treatment of Allergic Conjunctivitis

Dual-action agents that combine antihistamine and mast cell stabilizer properties (such as olopatadine, ketotifen, epinastine, and azelastine) are the most effective first-line treatment for allergic conjunctivitis due to their rapid onset of action and ability to both treat acute symptoms and prevent future episodes. 1

First-Line Treatments

Non-Pharmacological Approaches

• Wear sunglasses to create a barrier against airborne allergens 2
• Apply cold compresses to reduce inflammation and provide symptomatic relief 3, 2
• Use refrigerated artificial tears to dilute allergens and inflammatory mediators 3, 2
• Avoid eye rubbing as it can worsen symptoms 2
• Implement allergen avoidance strategies including hypoallergenic bedding and frequent clothes washing 3

Pharmacological Approaches

• Dual-action agents (antihistamine + mast cell stabilizer) are preferred first-line medications 1:
  • Olopatadine (Pataday, Patanol)
  • Ketotifen (Alaway, Zaditor)
  • Epinastine (Elestat)
  • Azelastine (Optivar)
• These medications have onset of action within 30 minutes and are suitable for both acute and longer-term treatment 3
• Ketotifen has been shown to have rapid onset (within 15 minutes) and extended duration of action (at least 8 hours) 4

Second-Line Treatments

• For mild allergic conjunctivitis, over-the-counter topical antihistamine/vasoconstrictor agents can be used 3
• Mast cell stabilizers (cromolyn, lodoxamide, nedocromil, pemirolast) are better for prophylactic or longer-term treatment due to their slow onset of action 3, 1
• Topical NSAIDs such as ketorolac (Acular) can provide temporary relief of ocular itching 3

Third-Line Treatments

• For inadequately controlled symptoms, a brief course (1-2 weeks) of topical corticosteroids with a low side-effect profile can be added 3, 1
• Loteprednol etabonate (Alrex) is indicated for the treatment of allergic conjunctivitis and has a reduced risk of causing increased intraocular pressure compared to other ocular corticosteroids 3, 5
• Baseline and periodic measurement of intraocular pressure is necessary when using corticosteroids 2

Treatment for Severe or Refractory Cases

• Topical cyclosporine or tacrolimus can be considered for severe cases 3, 2
• Allergen-specific immunotherapy may be beneficial for patients with inadequate control with topical medications 2
• Consultation with an allergist or ophthalmologist is recommended for difficult-to-control disease 1

Important Precautions

• Prolonged use of ocular vasoconstrictors/decongestants can lead to rebound hyperemia (conjunctivitis medicamentosa), although use limited to 10 days appears safe 3, 1
• Ocular corticosteroids should be reserved for more severe symptoms due to potential side effects including cataract formation, elevated intraocular pressure, and secondary infections 3, 1
• Oral antihistamines may worsen dry eye syndrome and impair the tear film's protective barrier 3, 1
• Punctal plugs should be avoided as they prevent flushing of allergens and inflammatory mediators 1

Treatment Algorithm

1. Start with non-pharmacological measures (cold compresses, artificial tears, allergen avoidance) 3, 2
2. For mild to moderate symptoms, use dual-action agents (antihistamine + mast cell stabilizer) 1
3. For persistent symptoms, add mast cell stabilizers for long-term control 3, 1
4. For severe or acute exacerbations, consider a short course (1-2 weeks) of topical corticosteroids with low side-effect profile 3, 1
5. For refractory cases, consider topical cyclosporine/tacrolimus or referral to specialist 2, 1

The Cochrane review confirms that topical antihistamines and mast cell stabilizers effectively reduce symptoms of allergic conjunctivitis compared to placebo, with no reported serious adverse events 6.