Current therapy of allergic conjunctivitis

Abstract

Allergic conjunctivitis is a common ocular disorder. The main clinical types of conjunctival allergic reactions are seasonal allergic conjunctivitis, perennial allergic conjunctivitis, atopic kerato-conjunctivitis, vernal keratoconjunctivitis (VKC), and giant papillary conjunctivitis. The pathophysiology of allergic conjunctivitis involves primarily a type I hypersensitivity mechanism, with release of histamine and other chemical mediators from mast cells; however, a type IV hypersensitivity with participation of secondary inflammatory cells, such as T-helper cells, eosinophils, and their chemical mediators, also plays a role. Current therapy of allergic conjunctivitis is based on general measures that aim at eliminating exposure to the allergen, and medical treatment. The main classes of drugs involved in medical therapy are antihistamines (used with or without vasoconstrictors), mast-cell stabilizers, nonsteroidal anti-inflammatory drugs, and corticosteroids. Topical immunosuppressive drugs, such as cyclosporine, have recently been used in severe VKC with good results. In addition, laser or surgical removal of the corneal plaques and shield ulcers of VKC has led to a better visual outcome. The future of allergic conjunctivitis treatment lies in a better understanding of the complex intercellular relationships that occur during the immune response to the offending allergen.