Vancomycin may cause immediate drug reactions (IDRs) via IgE- and/or MRGPRX2 pathways, often leading to misclassification and avoidance. However, true IgE-mediated IDRs are rare, with no serological sIgE evidence reported. Since IgG is more accessible and has been shown to correlate with drug-sIgE in IDR (e.g., penicillin, PEG), measuring vancomycin-sIgG in vancomycin-exposed individuals could be a logical first step in assessing vancomycin's immunogenicity frequency. Understanding a drug’s immunogenicity potential could improve IDR risk assessment. No strong vancomycin immunogenic profile was observed, aligning with the limited evidence for true vancomycin-induced IgE-mediated reactions. Future longitudinal studies are needed to clarify vancomycin-specific antibody dynamics.

Arango, S. A., Dispenza, M., Chichester, K., Adkinson, N. F., Phillips, E., Hamilton, R., & MacGlashan, D. (2025). Immunogenic Profiling of Vancomycin: Detecting Vancomycin-Specific IgG in Patients With and Without Vancomycin Infusion Reactions. Journal of Allergy and Clinical Immunology, 155(2), AB437.