Pharmacological treatment options for allergic rhinitis and asthma.

The inflammatory response that results in allergic rhinitis and asthma is complex and involves numerous cell types, such as lymphocytes, mast cells, and eosinophils, and mediators, such as histamine, arachidonic acid metabolites, toxic proteins, and cytokines. Therefore, many different classes of pharmacological agents, acting at various discrete points, can influence the symptoms induced by this process. The various classes of agents include antihistamines, decongestants, anticholinergics, leukotriene antagonists, beta-adrenoceptor agonists, theophylline, sodium cromoglycate and corticosteroids. In this article the mechanism of action of each of these classes is discussed, together with their use in allergic rhinitis and asthma.