Omalizumab is a humanized monoclonal anti-IgE antibody developed for the treatment of allergic diseases. It has demonstrated good efficacy in patients with intermittent and persisting allergic rhinitis and in patients with moderate-to-severe allergic asthma. Omalizumab results in a marked lowering of free IgE in serum and down-regulation of IgE receptors on circulating basophils. In addition, it reduces the inflow of eosinophils into nasal and bronchial tissue and the number of IgE-positive mast cells in the bronchial mucosa. Omalizumab treatment has also been shown to be associated with down-regulation of IgE receptors on circulating dendritic cells, suggesting that blocking IgE may also inhibit chronic aspects of allergic inflammation involving T cell-activation. Patients' clinical symptoms are attenuated and their quality of life improved by anti-IgE treatment with omalizumab; other medications effective in symptomatic treatment are therefore less necessary. Omalizumab's broad spectrum of efficacy emphasizes the central role of IgE in the allergic-inflammatory cascade. Further areas of applications in ENT medicine could be anticipated in other IgE-related illnesses, such as allergic rhinitis, food allergies, laryngitis and chronic allergy-related rhinosinusitis.