Clavulanic acid sensitization seems more involved in cutaneous than systemic reactions in amoxicilline-clavulanate drug reactions.

Summary: BLs allergy is considered a major health issue, as BLs are the most frequently involved in drug allergic reactions. Amoxicillin (AX) is the most frequently involved drug in sensitization among all BLs. AX is commercialized alone or combined to clavulanic acid (CLA) in order to increase the antibiotic spectrum. The growing prescriptions of AX-CLA formulations contributed to increase the role of CLA as an allergy inducer. At present, little is known about the clinical characteristics of hypersensitivity reactions to clavulanate. The aim of this study was to assess the difference in the prevalence of cutaneous vs systemic reactions in patients who had a documented history of allergic reactions to amoxicillin-clavulanate and tested positive for clavulanate or penicillin/amoxicillin. Our study suggests that patients who presented only muco-cutaneous reactions were more often sensitized to CLA rather than AX.