Allergic rhinitis is a highly prevalent respiratory disease, affecting up to 40% of the population in some countries, and has an important impact on quality of life. Although a number of different drug types are available for treating allergic rhinitis, antihistamines are currently considered first-line therapy. Newer antihistamines, such as fexofenadine, are very effective in suppressing symptoms and are largely free of side-effects. In addition, they have been shown to improve patient's quality of life. Some patients have residual symptoms despite the use of antihistamines and other available treatments. Moreover, most current treatments only relieve symptoms, and do not modify the course of the disease. Current research into the pathophysiology of the disease is opening many promising new avenues for improved treatments. Such possibilities include improving methods of immunotherapy, based on our greater understanding of the balance between Th1 and Th2 cells and of the cytokines that they produce; and targeting and blocking the effects of bradykinin, substance P, leukotrienes, IgE antibody, tryptase, platelet-activating factor and prostaglandins. Refinements of immunotherapy are particularly promising, as they may provide a permanent cure for the disease in an increasing number of patients. Furthermore, recent evidence has shown that early intervention in children with allergic rhinitis, by antihistamine treatment or immunotherapy, can reduce the risk of developing asthma. Improved understanding of the links between allergic rhinitis and asthma is likely to advance the treatment of both diseases.