Objective  To investigate the causative drugs, clinical characteristics, and prognostic factors of drug eruptions, and to provide evidence for clinical diagnosis, management, and risk assessment.

Methods  A retrospective analysis was conducted on 135 patients with drug eruptions who were hospitalized in the Department of Dermatology of the Third Affiliated Hospital of Sun Yat-sen University from January 2019 to December 2023. Clinical data including demographic characteristics, causative drugs, types of drug eruptions, laboratory findings, and treatment strategies were collected. Patients were classified into mild and severe drug eruption groups according to disease severity. In addition, cases were categorized into non-immune checkpoint inhibitors (ICIs) and ICIs groups. Latency periods among subgroups were compared by Kruskal-Wallis H test and Dunn’s test, and the influencing factors of hospitalization duration in patients with severe drug eruptions were performed by multivariate linear regression analysis.

Results  A total of 135 patients were included, comprising 56 cases (41.5%) of mild drug eruptions and 79 cases (58.5%) of severe drug eruptions. Antipyretic and analgesic drugs (n = 5) were the most common causative agents of mild drug eruptions, whereas allopurinol (n = 9) was the leading cause of severe drug eruptions. Since 2022, an increasing trend in severe drug eruptions associated with ICIs has been observed (n = 12). Significant differences in latency periods were found among different types of drug eruptions (H = 15.684, P = 0.014), with ICI-related drug eruptions showing significantly longer latency compared with non-ICIs. Multivariate linear regression analysis demonstrated that peak body temperature (β = 0.266, P = 0.010) and the lowest serum albumin level (β = −0.273, P = 0.023) were independent factors of hospitalization duration in patients with severe drug eruptions.

Conclusions Antipyretic and analgesic drugs are the main causative agents of mild drug eruptions, whereas allopurinol is the predominant cause of severe drug eruptions. Elevated body temperature and decreased serum albumin levels may serve as potential predictors of prolonged hospitalization duration. In recent years, the incidence of severe cutaneous adverse drug reactions induced by ICIs has shown an increasing trend, and ICI-related eruptions exhibit a longer latency period than those caused by non-ICIs. Therefore enhanced clinical awareness and monitoring are warranted.