Validation and Reproducibility of S.P.A.T. With Allergens

Inclusion Criteria: Adults (18-65y) with presence or absence of self-reported symptoms of inhalant allergy will be included. Exclusion Criteria: * Skin pathology like chronic or exuberant urticaria, dermographism, chronic dermatitis that needs daily treatment * Use of antihistaminic medication \< 7 days before the start of the study * Use of tricyclic antidepressants (antihistamine activity) \< 7 days before the start of the study * Use of topical corticoids on the forearm \< 7 days before the start of the study * Use of Omalizumab \< 6 months before the start of the study * Pregnancy: there is a remote possibility of inducing a systemic allergic reaction that could induce uterine contractions or necessitate the use of epinephrine (thought to cause constriction of the umbilical artery)