The role of antihistamines in atopic dermatitis.

Although several lines of evidence support a role for histamine in the pathogenesis of atopic dermatitis, antihistamines have generally offered only marginal therapeutic benefit. The efficacy of the classic antihistamines has been severely limited by sedative effects, demonstrating the need for improved, nonsedating agents. Multifunctional antihistamines, or third-generation "antiallergic" drugs, appear to offer a variety of advantages beyond their ability to inhibit histamine release, such as inhibition of mediator release and interference with eosinophil migration. Double-blind studies of high-dose regimens are needed to help clarify the therapeutic efficacy of these antiallergic drugs.