The evolution of pharmacotherapy for rhinitis and urticaria.

The efficacy of antihistamines in the treatment of allergic rhinitis and urticaria is compared. In treating allergic rhinitis, the new second- and third-generation antihistamines have multiple advantages including rapid onset of action, extended duration of action, and efficacy for nearly all the symptoms that are produced by allergen sensitization. These include non-nasal and nasal symptoms. These agents are generally nonsedating and can be administered either once or twice daily. There is minimal potentiation for QTC prolongation, and they are safe and effective as first-line therapies for seasonal allergic rhinitis. They are especially effective when combined with topical corticosteroids in reducing the whole constellation of symptomatology of allergic rhinitis. The treatment of chronic idiopathic urticaria should include second- and third-generation antihistamines as primary therapy. Additional therapy may include H2 antagonists, antihistamine-decongestant combinations, tricyclic antidepressants such as doxepin, and beta-adrenergic agonists including albuterol and epinephrine for acute angioedema. Corticosteroids may be required to treat significant exacerbations of chronic urticaria and/or to break a long-standing cycle of urticaria. Miscellaneous therapeutic agents include leukotriene antagonists combined with H1, H2 antagonists, calcium channel antagonists, plasmapheresis, cyclosporin and methotrexate.