https://www.hl7.org/fhir/DSTU2/allergyintolerance.html AllergyIntolerance API retrieves bundle with available record ids of clinical assessments of allergies or intolerances to medications only. This information can be used to assess an individual's propensity or potential risk to have an adverse reaction on future exposure to the specified substance or class of substances. Additionally, the response to this controller includes any recorded information or evidence of a harmful or undesirable physiological response event for the individual and triggered by exposure to the identified substance or class of substance. Responses to this controller can be narrowed using date ranges based on the encounter start and end dates. NOTE: The number of records returned can be limited and is defaulted to 500.