Over and beyond the avoidance of allergies, prophylactic measures can also prevent the development of lower airway disease from upper airway disease, for example, bronchial asthma from allergic rhinitis. A further protective effect can be achieved by reducing both prenatal and postnatal allergens. A major concept of prevention--not merely of pulmonary function changes and the development of allergies--is the avoidance of exposure to passive smoking. With regard to pharmacotherapeutic agents, both official approval for their use by the respective age group, and the dearth of study-based data need to be taken into account. To ensure the successful application of inhalative agents, the use of appropriate inhalation aids as also ensuring the correct inhalation technique are urgently recommended, particularly in the case of children and adolescents.