Adverse drug reactions involving the skin are commonly known as drug eruptions. Severe drug eruption may cause severe cutaneous adverse drug reactions (SCARs), which are considered to be fatal and life-threatening, including Stevens-Johnson syndrome (SJS), toxic epidermal necrolysis (TEN), acute generalized exanthematous pustulosis (AGEP), and drug reaction with eosinophilia and systemic symptoms (DRESS). Although cases are relatively rare, approximately 2% of hospitalized patients are affected by SCARs. There is an incidence of 2 to 7 cases/million per year of SJS/TEN and 1/1000 to 1/10,000 exposures to offending agents result in DRESS. However, the mortality rate of severe drug eruptions can reach up to 50%. SCARs represent a real medical emergency, and early identification and proper management are critical to survival. The common pathogenesis of severe drug eruptions includes genetic linkage with HLA- and non-HLA-genes, drug-specific T cell-mediated cytotoxicity, T cell receptor restriction, and cytotoxicity mechanisms. A multidisciplinary approach is required for acute management. Immediate withdrawal of potentially causative drugs and specific supportive treatment is of great importance. Immunoglobulins, systemic corticosteroids, and cyclosporine A are the most frequently used treatments for SCARs; additionally, new biologics and plasma exchange are reasonable strategies to reduce mortality. Although there are many treatment methods for severe drug eruption, controversies remain regarding the timing and dosage of drug eruption. Types, dosages, and indications of new biological agents, such as tumor necrosis factor antagonists, mepolizumab, and omalizumab, are still under exploration. This review summarizes the clinical characteristics, risk factors, pathogenesis, and treatment strategies of severe drug eruption to guide clinical management.

涉及皮肤的药物不良反应通常称为药疹。严重的药疹可能导致严重的皮肤药物不良反应（SCARs），被认为是致命和危及生命的，包括史蒂文斯-约翰逊综合征（SJS）、中毒性表皮坏死松解症（TEN）、急性全身发疹性脓疱病（AGEP）和嗜酸性粒细胞增多和全身症状（DRESS）的药物反应。尽管病例相对罕见，但大约 2% 的住院患者受到 SCAR 的影响。每年 SJS/TEN 的发病率为 2 至 7 例/百万，1/1000 至 1/10,000 的暴露于有害物质导致 DRESS。然而，严重药疹的死亡率可达50%。SCAR 代表了真正的医疗紧急情况，早期识别和适当管理对生存至关重要。严重药疹的常见发病机制包括与 HLA 和非 HLA 基因的遗传连锁、药物特异性 T 细胞介导的细胞毒性、T 细胞受体限制和细胞毒性机制。急性管理需要多学科方法。立即停用潜在的致病药物和特定的支持治疗非常重要。免疫球蛋白、全身性皮质类固醇和环孢素 A 是 SCAR 最常用的治疗方法；此外，新的生物制剂和血浆置换是降低死亡率的合理策略。重症药疹的治疗方法虽然很多，但关于药疹的时间和剂量仍存在争议。肿瘤坏死因子拮抗剂、美泊利单抗、奥马珠单抗等新型生物制剂的种类、剂量和适应症，仍在探索中。本文就重症药疹的临床特点、危险因素、发病机制及治疗策略进行总结，以指导临床管理。