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Allergen Class CodeSystem Code system

Canonical../CodeSystem/nexus-allergen-class
Statusdraft · 1.26.0
Contentcomplete
SourceFSH · JSON

What kind of thing an allergen is, carried as a second coding on AllergyIntolerance.code beside the substance's own SNOMED CT code.

This determines AllergyIntolerance.category rather than duplicating it -- each class maps onto exactly one R4 category, and drug and class both map onto medication. That is the point of the system: a reaction to one drug and a reaction to a whole drug class are the same R4 category and are not the same fact, and cross-sensitivity checking needs to tell them apart.

Read it by matching Coding.system. The substance coding and the class coding share one CodeableConcept and are in no guaranteed order.

Code Display Definition
drug Drug A single medicinal substance. Maps to AllergyIntolerance.category = medication.
class Drug class A class of medicinal substances rather than one of them -- penicillins, sulfonamides. Maps to AllergyIntolerance.category = medication, the same category a single drug maps to…
food Food A food or food constituent. Maps to AllergyIntolerance.category = food.
env Environmental A non-ingested environmental substance -- pollens, latex, animal dander, venoms. Maps to AllergyIntolerance.category = environment.
vaccine Vaccine A vaccine or a vaccine constituent. Maps to AllergyIntolerance.category = biologic.