This is the ValueSet that contains all the codes in CH AllergyIntolerance Reaction Substance (http://fhir.ch/ig/ch-allergyintolerance/ValueSet/CHAllergyIntoleranceReactionSubstanceValueSet) and CH AllergyIntolerance Reaction Substance (http://fhir.ch/ig/ch-allergyintolerance/ValueSet/CHAllergyIntoleranceReactionSubstanceValueSet). E.g. what you have to deal with if you get resources containing codes in either of them