Clinical Characteristics, Treatment, and Prognosis of Hydroxychloroquine‐Induced Acute Generalized Exanthematous Pustulosis

Background The clinical characteristics of hydroxychloroquine (HCQ)‐induced acute generalized exanthematous pustulosis (AGEP) remain inadequately defined. This research sought to define the incidence and clinical course of AGEP following HCQ administration. Methods We performed a retrospective analysis of clinical cases of HCQ‐induced AGEP by systematically reviewing both Chinese and English medical databases up to October 31, 2025. Results A total of 76 patients were included in the analysis, with a median age of 45 years (range: 9, 79), of which 65 (85.5%) were female. The median duration from the initiation of HCQ to the onset of symptoms was 5 days (range: 2, 122). In addition to the presence of nonfollicular, pinhead‐sized pustules on erythematous and edematous skin, patients frequently exhibited fever (73.9%) and pruritus (59.4%). Laboratory evaluations typically revealed elevated peripheral blood neutrophil counts, erythrocyte sedimentation rate, and C‐reactive protein levels in individuals with AGEP. Symptoms resolved in all patients with a median duration of 18.5 days (range: 5, 119) following the cessation of HCQ and appropriate management. Conclusion While HCQ is widely used in dermatology and rheumatology, AGEP remains a rare adverse event. Skin symptoms in patients taking HCQ should prompt consideration of this diagnosis. Prolonged latency of HCQ‐induced AGEP is predominantly observed in female patients with rheumatic conditions. Timely recognition and management of AGEP are critical to guide appropriate drug management and ensure patient safety.