New directions in antihistamine research

H-1 antihistamines have been a mainstay of therapy for allergic disorders for well over fifty years. These first generation antihistamines have largely been supplanted by the second generation compounds which lack the sedative effects of their first generation counterparts. However, over the past few decades it has become apparent that a number of mediators are released at various stages of the allergic response. It appears that current efforts to discover new antihistamines are focused on the incorporation of other activities (in addition to simple H-1 antagonism) to produce the third generation of antihistamines. This editorial will discuss recent activity in both the patent and primary literature, concentrating on the area of antihistamine research that exemplifies this trend.