IGHE and allergic disease: We elaborated on the increasing volume of evidence that allergy testing and serum IgE have poor prognostic and theragnostic value in asthma; we reviewed the complementary value of type-2 inflammatory biomarkers (blood eosinophils and Feno), spirometry, and adherence checking, and we emphasized the importance of evaluating and managing treatable type 2 comorbidities.