Table 1. Common reasons for mislabeling a patient as β-lactam allergic.

Misinterpretation of
– known predictable side effects as allergy (e.g., pure gastrointestinal symptoms due to alteration of the intestinal microbiome)
– infection-induced urticaria as an immediate-type drug reaction
– infection-induced viral exanthema as drug exanthema
– non-specific symptoms or somatoform reactions as allergy
– known reactions in the family as an indication of β-lactam allergy
– a fear of an allergy as an actual allergy (“I react to all medications”)