Leukotriene receptor antagonists: clinical potential in allergic rhinitis

Leukotrienes are potent pro-inflammatory mediators that have been shown to play a prominent role in the pathophysiology of asthma and associated allergic disorders including allergic rhinitis (AR) and atopic dermatitis (AD). In the treatment of these disorders, topical corticosteroids (TCS) are currently the most important anti-inflammatory agents, however, long-term application of TCS is associated with side-effects. Moreover, corticosteroids appeared not to inhibit the release of leukotrienes in humans in vivo. Therefore, leukotriene receptor antagonists (LTRAs) have been introduced into clinical practice and these specific oral drugs are currently registered as additive therapy in mild to moderate persistent asthma not controlled by inhaled corticosteroids. As for other allergic disorders, including AR, until recently only a few placebo-controlled studies with LTRAs have been performed. These (preliminary) data provide a basis for optimism, but clearly more long-term studies are needed to evaluate their clinical effectiveness, especially as add-on therapy.