Marie was correct in that FHIR seems to conflate non-allergic hypersensitivity (pseudoallergy) with allergy. "Adverse reactions may be: an allergy (typically type I hypersensitivity, plus other "allergy-like" reactions, including pseudoallergy)". FHIR distinguishes between allergy/pseudoallergy and intolerance but admits that practically they too are often lumped together . "In clinical practice distinguishing between allergy and intolerance is difficult and might not be practical. Often the term "allergy" is used rather generically and may overlap with "intolerance", and the boundaries between these concepts might not be well-defined or understood"