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One of the first questions that medical doctors and likewise nurses ask patients when performing a medical history is: Do you have any drug allergies? It is interesting that even at Medical School, students learn that asking about drug allergy belongs to the structured anamnesis obtaining procedure, but what is its impact and relevance? According to Gell and Coombs's classification described in 1963, immediate drug hypersensitivity reactions (IDHRs) are considered as Type 1 reactions, leading to mast cell and basophil degranulation. This classification encompasses IgEmediated reactions, but there are additional reactions that involve nonIgEmediated mechanisms. The understanding of phenotypes, endotypes, and biomarkers has improved the categorization of immediate DHRs.1 However, nonimmediate reactions are the most frequent in children, usually manifesting as maculopapular exanthema or delayedappearing urticaria.2 The incidence and prevalence of DHRs in children depends on drug consumption, with amoxicillin being the most frequent elicitor (AX), increasingly combined with clavulanic acid (CL). Indeed, Isabel TorresRojas et al. have analyzed the patterns of response of DHRs to βlactams in 530 children. Selective responders to AX were more likely to have nonimmediate reactions, while CL selectivity was exclusive to the nonimmediate reactor group.3 Nonclassic manifestations such as druginduced enterocolitis syndrome (DIES) may also appear and are described in this issue.4,5 The journal ́s virtual issue on “Drug Allergy” includes several studies published recently addressing novel management of DHRs in children, focusing on in vivo and in vitro diagnostic tools, the role of hidden allergens, the importance of delabeling, and how to prevent future episodes through drug desensitization. Drug allergy labels could have negative consequences, especially in target populations.6 Delabelling is a critical part of antimicrobial stewardship, which helps avoiding long hospitalizations and elevated costs.7 Moreover, a βlactam allergy is considered a risk factor for developing quinolone allergy in adults,8 and recently, Suleyman et al.9 have identified confirmed βlactam allergy as a risk factor for clarithromycin hypersensitivity in children, particularly when clarithromycin treatment is required after developing a rash with AXCL in sequential usage. New diagnostic perspectives are changing the paradigm of βlactam allergy management. Recent challenging data emphasize the safety of direct drug provocation test (DPT) in children with a suspicion of nonimmediate mild cutaneous reactions such as maculopapular eruption and delayedappearing urticaria and for benign immediate reactions such as urticaria/angioedema.10 Identifying lowrisk βlactam allergy children and proceeding directly to DPT could be safe and avoid a false label in adult life. In fact, a prospective study carried out by Chayaniss Pachasidchai et al.11 from January 2021 to April 2022, in which 154 children were included, concluded that the 2step direct oral DPT without prior skin test and continued for 5 days is an effective and safe method to delabel suspected βlactam allergies in lowrisk children. The tendency beyond reducing unnecessary tests in this population, standing for direct DPT, is to prioritize less timeconsuming protocols. In this sense, Giulia Liccioli et al.12 suggest that a single therapeutic dose administered on the 1st day of a DPT could be safe in the diagnostic workup of mild nonimmediate reactions to AX/CL. When patients are confirmed as allergic and the label is definitive, rapid drug desensitization (RDD) protocols have been developed to allow safe administration of the culprit drug if there is no alternative or the secondline treatment is less effective or more toxic.13 Saliha Esenboga et al.14 have studied the safety of RDD in children with chronic diseases who are allergic to their firstline therapy. In this article, 269 RDDs were performed successfully, being 90% free of breakthrough reactions. Moreover, premedication with omalizumab may facilitate RDD in specific phenotypes and allow the continuation of preferred treatment for those who have breakthrough reactions.15 Drug allergy labels could impact negatively patient's quality of life and life expectancy. Endophenotyping is crucial to correctly diagnose and treat patients based on in vivo and in vitro tests. Longterm management of DHRs encompasses RDD to maintain children in their first and best treatment option. The editorial team hopes you will enjoy this selection of articles provided in this virtual issue on drug allergy as well as the reviews provided to the issue.