Diagnosis and pharmacological management of allergic conjunctivitis

Background: Allergic conjunctivitis is an immune disease primarily attributed to a type 1 hypersensitivity reaction in the conjunctiva of the eye. Based on clinical findings and pathogenesis, allergic conjunctivitis is classified into the following subtypes: seasonal allergic conjunctivitis, perennial allergic conjunctivitis, atopic keratoconjunctivitis, vernal keratoconjunctivitis, and giant papillary conjunctivitis.Current Concepts: The recommended initial treatment for allergic conjunctivitis involves the use of dual-effect agents exerting both antihistamine and mast cell stabilizing effects. If symptoms persist despite the application of these agents, coexisting allergic rhinitis should be considered a possible contributing factor, as this condition can also lead to ocular symptoms. Concurrent treatment of allergic rhinitis is necessary. Although oral antihistamines effectively alleviate symptoms associated with allergic conjunctivitis, potential systemic side effects must be carefully considered, particularly in older individuals and children. Steroid eye drops should be used for limited durations to minimize side effects. Unlike seasonal and perennial allergic conjunctivitis, vernal keratoconjunctivitis, atopic keratoconjunctivitis, and giant papillary conjunctivitis involve both type 1 hypersensitivity reactions and type 4 hypersensitivity mediated by T cells. In cases where dual-effect agents or steroid eye drops fail to yield improvements, topical immunosuppressants such as cyclosporine A or tacrolimus can be effective.Discussion and Conclusion: The pharmacological treatment of allergic conjunctivitis involves the initial use of dual-effect agents, with concurrent treatment of allergic rhinitis if present. Importantly, atopic and vernal keratoconjunctivitis can potentially lead to permanent vision loss, necessitating the application of steroid eye drops or immunosuppressant eye drops.