Chlorhexidine generally has a good safety profile. However, allergic reactions are reported with increasing frequency. In China, it is rarely reported, and its characteristics are unknown. The purpose of this study was to summarize the experience of a Chinese allergy centre with chlorhexidine allergy.


We retrospectively reviewed all patients who underwent chlorhexidine allergy testing in the Allergy Centre of West China Hospital, Sichuan University in the period February 2018-May 2022 (n=43 patients) and included the patients diagnosed with chlorhexidine allergy for analysis.


Ten patients who were diagnosed by skin prick and serum specific IgE tests were included. They experienced a total of 30 allergic reactions to chlorhexidine (mean±standard deviation, 3.0 ± 1.3). Five patients experienced 6 allergic reactions (6/30, 20%) during general or local anaesthesia, and they may have been exposed to chlorhexidine via different routes. Only 1 allergic reaction (1/30, 3%) with exposure via a mouthwash. The other 23 allergic reactions (23/30, 77%) via a skin disinfectant; the route of exposure was intravenous (IV) cannulation in 22 allergic reactions (22/23, 96%) and broken skin in 1 allergic reaction (1/23, 4%). The symptoms included a quick onset and great severity. Two patients (2/10, 20%) had been accidentally re-exposed to chlorhexidine after diagnosis.


This study conducted in China showed that the majority of reactions to chlorhexidine were attributed to skin disinfectants, and IV cannulation was the most common exposure route; in general, however, chlorhexidine allergy was overlooked. The potential allergenicity of chlorhexidine used for skin preparationafter IV cannulation or should be considered in patients who develop allergic reactions perioperatively.