What is the best treatment for allergic conjunctivitis?

Best Treatment for Allergic Conjunctivitis

Dual-action agents (combined antihistamine and mast cell stabilizer) 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, 2

First-Line Treatment Options

• Cold compresses and irrigation with saline solution or refrigerated preservative-free artificial tears provide immediate symptomatic relief by diluting allergens and inflammatory mediators on the ocular surface 1, 2, 3
• Wearing sunglasses creates a barrier against airborne allergens and reduces exposure 3
• Implementing allergen avoidance strategies including hypoallergenic bedding, frequent clothes washing, and avoiding eye rubbing is crucial 1, 3
• Dual-action agents (antihistamine + mast cell stabilizer) have an onset within 30 minutes and are suitable for both acute relief and longer-term treatment 2

Second-Line Treatment Options

• Mast cell stabilizers alone (cromolyn, lodoxamide, nedocromil, pemirolast) are better for prophylactic or longer-term treatment due to their slow onset of action (several days) 1, 2
• Topical NSAIDs, such as ketorolac, can provide temporary relief of ocular itching caused by seasonal allergic conjunctivitis 1, 2
• Over-the-counter topical antihistamine/vasoconstrictor combinations can be used for mild allergic conjunctivitis, but prolonged use of vasoconstrictors can lead to rebound hyperemia (conjunctivitis medicamentosa) 2, 3

Third-Line Treatment Options

• For severe symptoms or acute exacerbations that don't respond to first and second-line treatments, a brief course (1-2 weeks) of topical corticosteroids with a low side-effect profile, such as loteprednol etabonate, can be added to the regimen 4, 1, 3
• Loteprednol etabonate 0.2% is FDA-approved for the temporary relief of signs and symptoms of seasonal allergic conjunctivitis 5
• Clinical studies have shown loteprednol etabonate 0.2% to be superior to placebo in reducing bulbar conjunctival injection and itching, beginning approximately 2 hours after instillation 5
• Baseline and periodic measurement of intraocular pressure and pupillary dilation should be performed to evaluate for glaucoma and cataract when using corticosteroids 4, 3

Treatment for Severe or Refractory Cases

• Topical cyclosporine 0.05% has been shown to be effective for severe vernal/atopic conjunctivitis and may allow for reduced use of topical steroids 4, 3
• Topical tacrolimus can also be considered for severe cases 1, 3
• For severe sight-threatening atopic keratoconjunctivitis that is not responsive to topical therapy, supratarsal injection of corticosteroid can be considered 4
• Consultation with an allergist or ophthalmologist may be beneficial for allergen-specific immunotherapy in patients with inadequate control with topical medications 3

Important Considerations and Precautions

• Oral antihistamines may worsen dry eye syndrome and impair the tear film's protective barrier, potentially worsening allergic conjunctivitis 4, 1, 2
• Punctal plugs should be avoided as they prevent flushing of allergens and inflammatory mediators from the ocular surface 4
• Patients with allergic conjunctivitis should avoid eye rubbing, which can worsen symptoms and potentially lead to keratoconus, especially in patients with atopic disease 1, 3
• Topical corticosteroids carry risks of increased intraocular pressure, cataract formation, and secondary infections, so they should be used cautiously and for limited periods 1, 5

Treatment Algorithm

1. Start with non-pharmacological measures (cold compresses, artificial tears, allergen avoidance) for all patients 2, 3
2. Add dual-action agents (antihistamine + mast cell stabilizer) for symptomatic relief and prevention 1, 2
3. If inadequate response, consider adding mast cell stabilizers or topical NSAIDs 1, 2
4. For severe or refractory symptoms, use a short course (1-2 weeks) of topical corticosteroids like loteprednol etabonate 0.2% 4, 5
5. For persistent severe cases, consider topical cyclosporine or tacrolimus and specialist referral 4, 1, 3