The steadily increasing prevalence of allergic disorders, including allergic rhinitis (AR), asthma, and atopic dermatitis, with global figures currently corresponding to more than 20% of the general population [
1‐
4] results in a relevant individual and social economic burden. For example, concerning AR, in a retrospective analysis performed in the 2000s using data from a US health plan covering about 15 million patients, the mean total costs per year related to rhinitis were $657 per patient, the primary contributor being outpatient visits [
5]. The economic burden includes direct costs, that are related to drug treatment and visits at physician office, and indirect costs, that are associated to reduced/missed work productivity [
6]. In the late 1990s the cost for AR in the US were estimated in $4.5 billion for direct and $3.4 billion for indirect costs, respectively, [
7] and by 2005 total expenditures to treat AR reached $11.2 billion [
8]. In Europe, a study conducted in 2003 found a mean annual cost of €1089 for child/adolescents and €1543 per adults, respectively, with predominance of indirect costs in adults (about 50%) compared with children (6%), in whom however the estimate did not include school absences [
9]. A probabilistic cost of illness study in Italy estimated a global economic burden associated with respiratory allergies and their main co-morbidities of €7.33 billion (95% CI: €5.99–€8.82). A percentage of 27.5% was associated with indirect costs and 72.5% with direct costs [
10]. A very recent study from UK on 1000 adults patients with seasonal AR demonstrated that limiting the assessment to absenteeism (on average, 4 days/year) a cost of £1.14 billion/year was estimated [
11]. Pharmacoeconomics is the scientific discipline that analyzes the value of different drug therapies, serving to guide the optimal allocation of healthcare resource by standardized and scientifically solid methods [
12]. From the pharmacoeconomic point of view, any drug treatment must be evaluated according to its cost-effectiveness, the cost referring to the resource expenditure for the intervention, that is usually measured in pecuniary terms [
13]. For example, in AR first generation antihistamines may impair mental performances (due to their sedating effects) more than in untreated patients [
14] and thus rise indirect cost. By a global therapeutic approach to AR, any preventive strategy that is aimed at reducing the severity of the rhinitis is likely to lessen its costs, and this particularly concerns allergen immunotherapy (AIT).