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We have reviewed with great interest the case report published by Belančić et al entitled ‘Afatinib-induced toxic epidermal necrolysis: A case report with a literature review’.1 This study presents an interesting and significant case in the fields of oncology and pharmacovigilance, focusing on a rare but severe adverse event in an oncological patient treated with afatinib. The research focuses on the detailed documentation of toxic epidermal necrolysis (TEN)/Stevens–Johnson syndrome (SJS), a potentially life-threatening condition that manifested 8 days after the initiation of drug therapy. The authors conducted a systematic literature review, identifying only five previous cases. This highlights the rarity of the event and the importance of accurately documenting it to expand knowledge of the drug’s side effects. The study provides valuable insights into the immunological mechanisms underlying TEN/SJS, with one of its strengths being the detailed presentation of the event, contributing to the scientific literature on drug safety. The clinical progression of TEN/SJS is documented with significant images, and the systematic literature review was conducted using the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) methodology. Methodologically, the authors performed an analysis of Eudravigilance and HALMED, demonstrating a rigorous approach to data collection and interpretation. This work has prompted us to further investigate this topic, focusing on adverse drug reactions (ADRs) reported in the U.S. Food and Drug Administration (FDA) Adverse Event Reporting System (FAERS),2 as this database was not analysed by Belančić et al. Our analysis included data from 2014 to 2024, focusing on ‘TEN’ and ‘SJS’ ADRs due to afatinib. Since TEN is a more severe form of SJS, the reactions were grouped as TEN/SJS. A total of 6272 afatinib-related ADR events were identified. The incidence of ADRs in the ‘Skin and subcutaneous tissue disorders’ class was 1707 (27%). Specifically, 23 cases (1.35%) were identified, of which 15 (0.88%) were SJS and 9 (0.52%) were TEN. All events were classified as ‘serious’, primarily affecting women and individuals aged 18–64 and 65–85 years (figure 1). These data confirm the rarity of the event and that these ADRs incur high healthcare costs, with an average expenditure of US$8061 for TEN patients and US$4457 for SJS patients. The main costs stem from hospitalisation, which increases with the length of stay and in cases of death.3 One of the main limitations of the study by Belančić et al is that being a single case report, the results cannot be generalised. It would have been useful to include details on long-term follow-up. It is important to note that pharmacovigilance analyses have limitations, such as reliance on spontaneous reports, which may be incomplete or subject to underreporting bias, and the lack of a direct comparison with control groups, making it difficult to establish a definitive causal relationship between a drug and an adverse event.4 The study does not provide information on the incidence of collected ADRs. This work represents a preliminary step towards understanding a serious adverse effect associated with the use of afatinib, highlighting the importance of pharmacovigilance and monitoring of patients treated with afatinib, emphasising the impact of the costs of SJS and TEN.