Purpose of review
Allergic conjunctivitis is an IgE-mediated inflammatory of conjunctiva. Despite the fact that histamine is a major mediator in this condition, use of topical antihistamines often gives only temporarily relief. Therapeutic agents aiming at inflammatory cascades of the disease are desirable particularly in cases with prolonged and severe allergic conjunctivitis. The article reviews these new treatment armamentariums with regard to their mechanism of actions and clinical efficacy.
Some second generation of antihistamines demonstrated anti-inflammatory properties such as inhibition of histamine release from mast cells as well as interference with the production cytokines and adhesion molecules from cord blood and conjunctival mast cells. Among these agents, ketotifen, epinastine and olopatadine are agents of major interest and are thus reviewed. Cromolyn, nedocromil, topical corticosteroids and immunotherapy, especially sublingual immunotherapy, are among other modes of therapy examined. Finally, the review focuses on cyclosporine A and tacrolimus, immunomodulators that have been extensively studied in the therapy of severe conjunctivitis such as atopic and vernal keratoconjunctivitis with promising results.
Several immunomodulatory options are currently available for treatment of allergic conjunctivitis. These therapeutic availabilities bring about a better therapeutic outcome for patients with allergic conjunctivitis, particularly those on the severe end of the spectrum.