Allergic asthma

**Definition:** Allergic asthma is the most easily recognised asthma phenotype, which often commences in childhood and is associated with a past and/or family history of allergic diseases such as eczema, allergic rhinitis, or food or drug allergy. Examination of the induced sputum of these patients before treatment often reveals eosinophilic airway inflammation. The main trigger is the exposure to inhaled allergens, such as dust mite and pollens, to which the affected individual has previously been sensitized. Patients with this asthma phenotype usually respond well to inhaled corticosteroid (ICS) treatment and specific allergen-immunotherapy.