US Core Implementation Guide
7.0.0 - CI Build United States of America flag

US Core Implementation Guide, published by HL7 International / Cross-Group Projects. This guide is not an authorized publication; it is the continuous build for version 7.0.0 built by the FHIR (HL7® FHIR® Standard) CI Build. This version is based on the current content of https://github.com/HL7/US-Core/ and changes regularly. See the Directory of published versions

Resource Profile: USCoreAllergyIntolerance - Detailed Descriptions

Page standards status: Trial-use Maturity Level: 3

Definitions for the us-core-allergyintolerance resource profile.

Guidance on how to interpret the contents of this table can be found here

0. AllergyIntolerance
Must Supportfalse
2. AllergyIntolerance.clinicalStatus
BindingThe codes SHALL be taken from AllergyIntoleranceClinicalStatusCodes
(required to http://hl7.org/fhir/ValueSet/allergyintolerance-clinical)
Must Supporttrue
4. AllergyIntolerance.verificationStatus
BindingThe codes SHALL be taken from AllergyIntoleranceVerificationStatusCodes
(required to http://hl7.org/fhir/ValueSet/allergyintolerance-verification)
Must Supporttrue
6. AllergyIntolerance.code
Control1..?
BindingUnless not suitable, these codes SHALL be taken from Common substances for allergy and intolerance documentation including refutations .
(extensible to http://cts.nlm.nih.gov/fhir/ValueSet/2.16.840.1.113762.1.4.1186.8)
Must Supporttrue
8. AllergyIntolerance.patient
TypeReference(US Core Patient Profile)
Must Supporttrue
10. AllergyIntolerance.reaction
Must Supporttrue
12. AllergyIntolerance.reaction.manifestation
BindingUnless not suitable, these codes SHALL be taken from SNOMEDCTClinicalFindings
(extensible to http://hl7.org/fhir/ValueSet/clinical-findings)
Must Supporttrue

Guidance on how to interpret the contents of this table can be found here

0. AllergyIntolerance
Definition

Risk of harmful or undesirable, physiological response which is unique to an individual and associated with exposure to a substance.

ShortAllergy or Intolerance (generally: Risk of adverse reaction to a substance)
Comments

Substances include, but are not limited to: a therapeutic substance administered correctly at an appropriate dosage for the individual; food; material derived from plants or animals; or venom from insect stings.

Control0..*
Is Modifierfalse
Must Supportfalse
Summaryfalse
Alternate NamesAllergy, Intolerance, Adverse Reaction
Invariantsait-1: AllergyIntolerance.clinicalStatus SHALL be present if verificationStatus is not entered-in-error. (verificationStatus.coding.where(system = 'http://terminology.hl7.org/CodeSystem/allergyintolerance-verification' and code = 'entered-in-error').exists() or clinicalStatus.exists())
ait-2: AllergyIntolerance.clinicalStatus SHALL NOT be present if verification Status is entered-in-error (verificationStatus.coding.where(system = 'http://terminology.hl7.org/CodeSystem/allergyintolerance-verification' and code = 'entered-in-error').empty() or clinicalStatus.empty())
dom-2: If the resource is contained in another resource, it SHALL NOT contain nested Resources (contained.contained.empty())
dom-3: If the resource is contained in another resource, it SHALL be referred to from elsewhere in the resource or SHALL refer to the containing resource (contained.where((('#'+id in (%resource.descendants().reference | %resource.descendants().as(canonical) | %resource.descendants().as(uri) | %resource.descendants().as(url))) or descendants().where(reference = '#').exists() or descendants().where(as(canonical) = '#').exists() or descendants().where(as(canonical) = '#').exists()).not()).trace('unmatched', id).empty())
dom-4: If a resource is contained in another resource, it SHALL NOT have a meta.versionId or a meta.lastUpdated (contained.meta.versionId.empty() and contained.meta.lastUpdated.empty())
dom-5: If a resource is contained in another resource, it SHALL NOT have a security label (contained.meta.security.empty())
dom-6: A resource should have narrative for robust management (text.`div`.exists())
ait-1: AllergyIntolerance.clinicalStatus SHALL be present if verificationStatus is not entered-in-error. (verificationStatus.coding.where(system = 'http://terminology.hl7.org/CodeSystem/allergyintolerance-verification' and code = 'entered-in-error').exists() or clinicalStatus.exists())
ait-2: AllergyIntolerance.clinicalStatus SHALL NOT be present if verification Status is entered-in-error (verificationStatus.coding.where(system = 'http://terminology.hl7.org/CodeSystem/allergyintolerance-verification' and code = 'entered-in-error').empty() or clinicalStatus.empty())
2. AllergyIntolerance.implicitRules
Definition

A reference to a set of rules that were followed when the resource was constructed, and which must be understood when processing the content. Often, this is a reference to an implementation guide that defines the special rules along with other profiles etc.

ShortA set of rules under which this content was created
Comments

Asserting this rule set restricts the content to be only understood by a limited set of trading partners. This inherently limits the usefulness of the data in the long term. However, the existing health eco-system is highly fractured, and not yet ready to define, collect, and exchange data in a generally computable sense. Wherever possible, implementers and/or specification writers should avoid using this element. Often, when used, the URL is a reference to an implementation guide that defines these special rules as part of it's narrative along with other profiles, value sets, etc.

Control0..1
Typeuri
Is Modifiertrue because This element is labeled as a modifier because the implicit rules may provide additional knowledge about the resource that modifies it's meaning or interpretation
Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
Summarytrue
Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
4. AllergyIntolerance.modifierExtension
Definition

May be used to represent additional information that is not part of the basic definition of the resource and that modifies the understanding of the element that contains it and/or the understanding of the containing element's descendants. Usually modifier elements provide negation or qualification. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer is allowed to define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. Applications processing a resource are required to check for modifier extensions.

Modifier extensions SHALL NOT change the meaning of any elements on Resource or DomainResource (including cannot change the meaning of modifierExtension itself).

ShortExtensions that cannot be ignored
Comments

There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone.

Control0..*
TypeExtension
Is Modifiertrue because Modifier extensions are expected to modify the meaning or interpretation of the resource that contains them
Summaryfalse
Requirements

Modifier extensions allow for extensions that cannot be safely ignored to be clearly distinguished from the vast majority of extensions which can be safely ignored. This promotes interoperability by eliminating the need for implementers to prohibit the presence of extensions. For further information, see the definition of modifier extensions.

Alternate Namesextensions, user content
Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
ext-1: Must have either extensions or value[x], not both (extension.exists() != value.exists())
6. AllergyIntolerance.clinicalStatus
Definition

The clinical status of the allergy or intolerance.

Shortactive | inactive | resolved
Comments

Refer to discussion if clincalStatus is missing data. The data type is CodeableConcept because clinicalStatus has some clinical judgment involved, such that there might need to be more specificity than the required FHIR value set allows. For example, a SNOMED coding might allow for additional specificity.

Control0..1
This element is affected by the following invariants: ait-1, ait-2
BindingThe codes SHALL be taken from AllergyIntoleranceClinicalStatusCodeshttp://hl7.org/fhir/ValueSet/allergyintolerance-clinical|4.0.1
(required to http://hl7.org/fhir/ValueSet/allergyintolerance-clinical)
TypeCodeableConcept
Is Modifiertrue because This element is labeled as a modifier because the status contains the codes inactive and resolved that mark the AllergyIntolerance as no longer active.
Must Supporttrue
Summarytrue
Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
8. AllergyIntolerance.verificationStatus
Definition

Assertion about certainty associated with the propensity, or potential risk, of a reaction to the identified substance (including pharmaceutical product).

Shortunconfirmed | confirmed | refuted | entered-in-error
Comments

The data type is CodeableConcept because verificationStatus has some clinical judgment involved, such that there might need to be more specificity than the required FHIR value set allows. For example, a SNOMED coding might allow for additional specificity.

Control0..1
This element is affected by the following invariants: ait-1, ait-2
BindingThe codes SHALL be taken from AllergyIntoleranceVerificationStatusCodeshttp://hl7.org/fhir/ValueSet/allergyintolerance-verification|4.0.1
(required to http://hl7.org/fhir/ValueSet/allergyintolerance-verification)
TypeCodeableConcept
Is Modifiertrue because This element is labeled as a modifier because the status contains the codes refuted and entered-in-error that mark the AllergyIntolerance as not currently valid.
Must Supporttrue
Summarytrue
Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
10. AllergyIntolerance.code
Definition

Code for an allergy or intolerance statement (either a positive or a negated/excluded statement). This may be a code for a substance or pharmaceutical product that is considered to be responsible for the adverse reaction risk (e.g., "Latex"), an allergy or intolerance condition (e.g., "Latex allergy"), or a negated/excluded code for a specific substance or class (e.g., "No latex allergy") or a general or categorical negated statement (e.g., "No known allergy", "No known drug allergies"). Note: the substance for a specific reaction may be different from the substance identified as the cause of the risk, but it must be consistent with it. For instance, it may be a more specific substance (e.g. a brand medication) or a composite product that includes the identified substance. It must be clinically safe to only process the 'code' and ignore the 'reaction.substance'. If a receiving system is unable to confirm that AllergyIntolerance.reaction.substance falls within the semantic scope of AllergyIntolerance.code, then the receiving system should ignore AllergyIntolerance.reaction.substance.

ShortCode that identifies the allergy or intolerance
Comments

It is strongly recommended that this element be populated using a terminology, where possible. For example, some terminologies used include RxNorm, SNOMED CT, DM+D, NDFRT, ICD-9, IDC-10, UNII, and ATC. Plain text should only be used if there is no appropriate terminology available. Additional details can be specified in the text.

When a substance or product code is specified for the 'code' element, the "default" semantic context is that this is a positive statement of an allergy or intolerance (depending on the value of the 'type' element, if present) condition to the specified substance/product. In the corresponding SNOMED CT allergy model, the specified substance/product is the target (destination) of the "Causative agent" relationship.

The 'substanceExposureRisk' extension is available as a structured and more flexible alternative to the 'code' element for making positive or negative allergy or intolerance statements. This extension provides the capability to make "no known allergy" (or "no risk of adverse reaction") statements regarding any coded substance/product (including cases when a pre-coordinated "no allergy to x" concept for that substance/product does not exist). If the 'substanceExposureRisk' extension is present, the AllergyIntolerance.code element SHALL be omitted.

Control10..1
BindingUnless not suitable, these codes SHALL be taken from For example codes, see Common substances for allergy and intolerance documentation including refutations .http://hl7.org/fhir/ValueSet/allergyintolerance-code
(extensible to http://cts.nlm.nih.gov/fhir/ValueSet/2.16.840.1.113762.1.4.1186.8)
TypeCodeableConcept
Is Modifierfalse
Must Supporttrue
Summarytrue
Alternate NamesCode
Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
12. AllergyIntolerance.patient
Definition

The patient who has the allergy or intolerance.

ShortWho the sensitivity is for
Control1..1
TypeReference(US Core Patient Profile, Patient)
Is Modifierfalse
Must Supporttrue
Summarytrue
Alternate NamesPatient
Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
14. AllergyIntolerance.reaction
Definition

Details about each adverse reaction event linked to exposure to the identified substance.

ShortAdverse Reaction Events linked to exposure to substance
Control0..*
TypeBackboneElement
Is Modifierfalse
Must Supporttrue
Summaryfalse
Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
16. AllergyIntolerance.reaction.modifierExtension
Definition

May be used to represent additional information that is not part of the basic definition of the element and that modifies the understanding of the element in which it is contained and/or the understanding of the containing element's descendants. Usually modifier elements provide negation or qualification. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. Applications processing a resource are required to check for modifier extensions.

Modifier extensions SHALL NOT change the meaning of any elements on Resource or DomainResource (including cannot change the meaning of modifierExtension itself).

ShortExtensions that cannot be ignored even if unrecognized
Comments

There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone.

Control0..*
TypeExtension
Is Modifiertrue because Modifier extensions are expected to modify the meaning or interpretation of the element that contains them
Summarytrue
Requirements

Modifier extensions allow for extensions that cannot be safely ignored to be clearly distinguished from the vast majority of extensions which can be safely ignored. This promotes interoperability by eliminating the need for implementers to prohibit the presence of extensions. For further information, see the definition of modifier extensions.

Alternate Namesextensions, user content, modifiers
Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
ext-1: Must have either extensions or value[x], not both (extension.exists() != value.exists())
18. AllergyIntolerance.reaction.manifestation
Definition

Clinical symptoms and/or signs that are observed or associated with the adverse reaction event.

ShortClinical symptoms/signs associated with the Event
Comments

Manifestation can be expressed as a single word, phrase or brief description. For example: nausea, rash or no reaction. It is preferable that manifestation should be coded with a terminology, where possible. The values entered here may be used to display on an application screen as part of a list of adverse reactions, as recommended in the UK NHS CUI guidelines. Terminologies commonly used include, but are not limited to, SNOMED CT or ICD10.

Control1..*
BindingUnless not suitable, these codes SHALL be taken from For example codes, see SNOMEDCTClinicalFindingshttp://hl7.org/fhir/ValueSet/clinical-findings
(extensible to http://hl7.org/fhir/ValueSet/clinical-findings)
TypeCodeableConcept
Is Modifierfalse
Must Supporttrue
Summaryfalse
Alternate NamesSymptoms, Signs
Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))

Guidance on how to interpret the contents of this table can be found here

0. AllergyIntolerance
Definition

icon Changed:

Risk of harmful or undesirable, physiological response which is unique to an individual and associated with exposure to a substance.

ShortAllergy or Intolerance (generally: Risk of adverse reaction to a substance)
Comments

icon Changed:

Substances include, but are not limited to: a therapeutic substance administered correctly at an appropriate dosage for the individual; food; material derived from plants or animals; or venom from insect stings.

Control0..*
Is Modifierfalse
Must Supportfalse
Summaryfalse
Alternate NamesAllergy, Intolerance, Adverse Reaction
Invariantsait-1: AllergyIntolerance.clinicalStatus SHALL be present if verificationStatus is not entered-in-error. (verificationStatus.coding.where(system = 'http://terminology.hl7.org/CodeSystem/allergyintolerance-verification' and code = 'entered-in-error').exists() or clinicalStatus.exists())
ait-2: AllergyIntolerance.clinicalStatus SHALL NOT be present if verification Status is entered-in-error (verificationStatus.coding.where(system = 'http://terminology.hl7.org/CodeSystem/allergyintolerance-verification' and code = 'entered-in-error').empty() or clinicalStatus.empty())
dom-2: If the resource is contained in another resource, it SHALL NOT contain nested Resources (contained.contained.empty())
dom-3: If the resource is contained in another resource, it SHALL be referred to from elsewhere in the resource or SHALL refer to the containing resource (contained.where((('#'+id in (%resource.descendants().reference | %resource.descendants().as(canonical) | %resource.descendants().as(uri) | %resource.descendants().as(url))) or descendants().where(reference = '#').exists() or descendants().where(as(canonical) = '#').exists() or descendants().where(as(canonical) = '#').exists()).not()).trace('unmatched', id).empty())
dom-4: If a resource is contained in another resource, it SHALL NOT have a meta.versionId or a meta.lastUpdated (contained.meta.versionId.empty() and contained.meta.lastUpdated.empty())
dom-5: If a resource is contained in another resource, it SHALL NOT have a security label (contained.meta.security.empty())
dom-6: A resource should have narrative for robust management (text.`div`.exists())
2. AllergyIntolerance.id
Definition

The logical id of the resource, as used in the URL for the resource. Once assigned, this value never changes.

ShortLogical id of this artifact
Comments

The only time that a resource does not have an id is when it is being submitted to the server using a create operation.

Control0..1
Typeid
Is Modifierfalse
Summarytrue
4. AllergyIntolerance.meta
Definition

The metadata about the resource. This is content that is maintained by the infrastructure. Changes to the content might not always be associated with version changes to the resource.

ShortMetadata about the resource
Control0..1
TypeMeta
Is Modifierfalse
Summarytrue
Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
6. AllergyIntolerance.implicitRules
Definition

A reference to a set of rules that were followed when the resource was constructed, and which must be understood when processing the content. Often, this is a reference to an implementation guide that defines the special rules along with other profiles etc.

ShortA set of rules under which this content was created
Comments

Asserting this rule set restricts the content to be only understood by a limited set of trading partners. This inherently limits the usefulness of the data in the long term. However, the existing health eco-system is highly fractured, and not yet ready to define, collect, and exchange data in a generally computable sense. Wherever possible, implementers and/or specification writers should avoid using this element. Often, when used, the URL is a reference to an implementation guide that defines these special rules as part of it's narrative along with other profiles, value sets, etc.

Control0..1
Typeuri
Is Modifiertrue because This element is labeled as a modifier because the implicit rules may provide additional knowledge about the resource that modifies it's meaning or interpretation
Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
Summarytrue
Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
8. AllergyIntolerance.language
Definition

The base language in which the resource is written.

ShortLanguage of the resource content
Comments

Language is provided to support indexing and accessibility (typically, services such as text to speech use the language tag). The html language tag in the narrative applies to the narrative. The language tag on the resource may be used to specify the language of other presentations generated from the data in the resource. Not all the content has to be in the base language. The Resource.language should not be assumed to apply to the narrative automatically. If a language is specified, it should it also be specified on the div element in the html (see rules in HTML5 for information about the relationship between xml:lang and the html lang attribute).

Control0..1
BindingThe codes SHOULD be taken from CommonLanguages
(preferred to http://hl7.org/fhir/ValueSet/languages)

A human language.

Additional BindingsPurpose
AllLanguagesMax Binding
Typecode
Is Modifierfalse
Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
Summaryfalse
Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
10. AllergyIntolerance.text
Definition

A human-readable narrative that contains a summary of the resource and can be used to represent the content of the resource to a human. The narrative need not encode all the structured data, but is required to contain sufficient detail to make it "clinically safe" for a human to just read the narrative. Resource definitions may define what content should be represented in the narrative to ensure clinical safety.

ShortText summary of the resource, for human interpretation
Comments

Contained resources do not have narrative. Resources that are not contained SHOULD have a narrative. In some cases, a resource may only have text with little or no additional discrete data (as long as all minOccurs=1 elements are satisfied). This may be necessary for data from legacy systems where information is captured as a "text blob" or where text is additionally entered raw or narrated and encoded information is added later.

Control0..1
TypeNarrative
Is Modifierfalse
Summaryfalse
Alternate Namesnarrative, html, xhtml, display
Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
12. AllergyIntolerance.contained
Definition

These resources do not have an independent existence apart from the resource that contains them - they cannot be identified independently, and nor can they have their own independent transaction scope.

ShortContained, inline Resources
Comments

This should never be done when the content can be identified properly, as once identification is lost, it is extremely difficult (and context dependent) to restore it again. Contained resources may have profiles and tags In their meta elements, but SHALL NOT have security labels.

Control0..*
TypeResource
Is Modifierfalse
Summaryfalse
Alternate Namesinline resources, anonymous resources, contained resources
14. AllergyIntolerance.extension
Definition

May be used to represent additional information that is not part of the basic definition of the resource. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension.

ShortAdditional content defined by implementations
Comments

There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone.

Control0..*
TypeExtension
Is Modifierfalse
Summaryfalse
Alternate Namesextensions, user content
Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
ext-1: Must have either extensions or value[x], not both (extension.exists() != value.exists())
16. AllergyIntolerance.modifierExtension
Definition

May be used to represent additional information that is not part of the basic definition of the resource and that modifies the understanding of the element that contains it and/or the understanding of the containing element's descendants. Usually modifier elements provide negation or qualification. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer is allowed to define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. Applications processing a resource are required to check for modifier extensions.

Modifier extensions SHALL NOT change the meaning of any elements on Resource or DomainResource (including cannot change the meaning of modifierExtension itself).

ShortExtensions that cannot be ignored
Comments

There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone.

Control0..*
TypeExtension
Is Modifiertrue because Modifier extensions are expected to modify the meaning or interpretation of the resource that contains them
Summaryfalse
Requirements

Modifier extensions allow for extensions that cannot be safely ignored to be clearly distinguished from the vast majority of extensions which can be safely ignored. This promotes interoperability by eliminating the need for implementers to prohibit the presence of extensions. For further information, see the definition of modifier extensions.

Alternate Namesextensions, user content
Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
ext-1: Must have either extensions or value[x], not both (extension.exists() != value.exists())
18. AllergyIntolerance.identifier
Definition

Business identifiers assigned to this AllergyIntolerance by the performer or other systems which remain constant as the resource is updated and propagates from server to server.

ShortExternal ids for this item
Comments

This is a business identifier, not a resource identifier (see discussion). It is best practice for the identifier to only appear on a single resource instance, however business practices may occasionally dictate that multiple resource instances with the same identifier can exist - possibly even with different resource types. For example, multiple Patient and a Person resource instance might share the same social insurance number.

NoteThis is a business identifier, not a resource identifier (see discussion)
Control0..*
TypeIdentifier
Is Modifierfalse
Summarytrue
Requirements

Allows identification of the AllergyIntolerance as it is known by various participating systems and in a way that remains consistent across servers.

Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
20. AllergyIntolerance.clinicalStatus
Definition

The clinical status of the allergy or intolerance.

Shortactive | inactive | resolved
Comments

Refer to discussion if clincalStatus is missing data. The data type is CodeableConcept because clinicalStatus has some clinical judgment involved, such that there might need to be more specificity than the required FHIR value set allows. For example, a SNOMED coding might allow for additional specificity.

Control0..1
This element is affected by the following invariants: ait-1, ait-2
BindingThe codes SHALL be taken from AllergyIntoleranceClinicalStatusCodes
(required to http://hl7.org/fhir/ValueSet/allergyintolerance-clinical)
TypeCodeableConcept
Is Modifiertrue because This element is labeled as a modifier because the status contains the codes inactive and resolved that mark the AllergyIntolerance as no longer active.
Must Supporttrue
Summarytrue
Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
22. AllergyIntolerance.verificationStatus
Definition

Assertion about certainty associated with the propensity, or potential risk, of a reaction to the identified substance (including pharmaceutical product).

Shortunconfirmed | confirmed | refuted | entered-in-error
Comments

The data type is CodeableConcept because verificationStatus has some clinical judgment involved, such that there might need to be more specificity than the required FHIR value set allows. For example, a SNOMED coding might allow for additional specificity.

Control0..1
This element is affected by the following invariants: ait-1, ait-2
BindingThe codes SHALL be taken from AllergyIntoleranceVerificationStatusCodes
(required to http://hl7.org/fhir/ValueSet/allergyintolerance-verification)
TypeCodeableConcept
Is Modifiertrue because This element is labeled as a modifier because the status contains the codes refuted and entered-in-error that mark the AllergyIntolerance as not currently valid.
Must Supporttrue
Summarytrue
Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
24. AllergyIntolerance.type
Definition

Identification of the underlying physiological mechanism for the reaction risk.

Shortallergy | intolerance - Underlying mechanism (if known)
Comments

Allergic (typically immune-mediated) reactions have been traditionally regarded as an indicator for potential escalation to significant future risk. Contemporary knowledge suggests that some reactions previously thought to be immune-mediated are, in fact, non-immune, but in some cases can still pose a life threatening risk. It is acknowledged that many clinicians might not be in a position to distinguish the mechanism of a particular reaction. Often the term "allergy" is used rather generically and may overlap with the use of "intolerance" - in practice the boundaries between these two concepts might not be well-defined or understood. This data element is included nevertheless, because many legacy systems have captured this attribute. Immunologic testing may provide supporting evidence for the basis of the reaction and the causative substance, but no tests are 100% sensitive or specific for sensitivity to a particular substance. If, as is commonly the case, it is unclear whether the reaction is due to an allergy or an intolerance, then the type element should be omitted from the resource.

Control0..1
BindingThe codes SHALL be taken from AllergyIntoleranceType
(required to http://hl7.org/fhir/ValueSet/allergy-intolerance-type|4.0.1)

Identification of the underlying physiological mechanism for a Reaction Risk.

Typecode
Is Modifierfalse
Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
Summarytrue
Alternate NamesCategory, Class
Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
26. AllergyIntolerance.category
Definition

Category of the identified substance.

Shortfood | medication | environment | biologic
Comments

This data element has been included because it is currently being captured in some clinical systems. This data can be derived from the substance where coding systems are used, and is effectively redundant in that situation. When searching on category, consider the implications of AllergyIntolerance resources without a category. For example, when searching on category = medication, medication allergies that don't have a category valued will not be returned. Refer to search for more information on how to search category with a :missing modifier to get allergies that don't have a category. Additionally, category should be used with caution because category can be subjective based on the sender.

Control0..*
BindingThe codes SHALL be taken from AllergyIntoleranceCategory
(required to http://hl7.org/fhir/ValueSet/allergy-intolerance-category|4.0.1)

Category of an identified substance associated with allergies or intolerances.

Typecode
Is Modifierfalse
Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
Summarytrue
Alternate NamesCategory, Type, Reaction Type, Class
Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
28. AllergyIntolerance.criticality
Definition

Estimate of the potential clinical harm, or seriousness, of the reaction to the identified substance.

Shortlow | high | unable-to-assess
Comments

The default criticality value for any propensity to an adverse reaction should be 'Low Risk', indicating at the very least a relative contraindication to deliberate or voluntary exposure to the substance. 'High Risk' is flagged if the clinician has identified a propensity for a more serious or potentially life-threatening reaction, such as anaphylaxis, and implies an absolute contraindication to deliberate or voluntary exposure to the substance. If this element is missing, the criticality is unknown (though it may be known elsewhere). Systems that capture a severity at the condition level are actually representing the concept of criticality whereas the severity documented at the reaction level is representing the true reaction severity. Existing systems that are capturing both condition criticality and reaction severity may use the term "severity" to represent both. Criticality is the worst it could be in the future (i.e. situation-agnostic) whereas severity is situation-dependent.

Control0..1
BindingThe codes SHALL be taken from AllergyIntoleranceCriticality
(required to http://hl7.org/fhir/ValueSet/allergy-intolerance-criticality|4.0.1)

Estimate of the potential clinical harm, or seriousness, of a reaction to an identified substance.

Typecode
Is Modifierfalse
Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
Summarytrue
Alternate NamesSeverity, Seriousness, Contra-indication, Risk
Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
30. AllergyIntolerance.code
Definition

Code for an allergy or intolerance statement (either a positive or a negated/excluded statement). This may be a code for a substance or pharmaceutical product that is considered to be responsible for the adverse reaction risk (e.g., "Latex"), an allergy or intolerance condition (e.g., "Latex allergy"), or a negated/excluded code for a specific substance or class (e.g., "No latex allergy") or a general or categorical negated statement (e.g., "No known allergy", "No known drug allergies"). Note: the substance for a specific reaction may be different from the substance identified as the cause of the risk, but it must be consistent with it. For instance, it may be a more specific substance (e.g. a brand medication) or a composite product that includes the identified substance. It must be clinically safe to only process the 'code' and ignore the 'reaction.substance'. If a receiving system is unable to confirm that AllergyIntolerance.reaction.substance falls within the semantic scope of AllergyIntolerance.code, then the receiving system should ignore AllergyIntolerance.reaction.substance.

ShortCode that identifies the allergy or intolerance
Comments

It is strongly recommended that this element be populated using a terminology, where possible. For example, some terminologies used include RxNorm, SNOMED CT, DM+D, NDFRT, ICD-9, IDC-10, UNII, and ATC. Plain text should only be used if there is no appropriate terminology available. Additional details can be specified in the text.

When a substance or product code is specified for the 'code' element, the "default" semantic context is that this is a positive statement of an allergy or intolerance (depending on the value of the 'type' element, if present) condition to the specified substance/product. In the corresponding SNOMED CT allergy model, the specified substance/product is the target (destination) of the "Causative agent" relationship.

The 'substanceExposureRisk' extension is available as a structured and more flexible alternative to the 'code' element for making positive or negative allergy or intolerance statements. This extension provides the capability to make "no known allergy" (or "no risk of adverse reaction") statements regarding any coded substance/product (including cases when a pre-coordinated "no allergy to x" concept for that substance/product does not exist). If the 'substanceExposureRisk' extension is present, the AllergyIntolerance.code element SHALL be omitted.

Control1..1
BindingUnless not suitable, these codes SHALL be taken from Common substances for allergy and intolerance documentation including refutations .
(extensible to http://cts.nlm.nih.gov/fhir/ValueSet/2.16.840.1.113762.1.4.1186.8)
TypeCodeableConcept
Is Modifierfalse
Must Supporttrue
Summarytrue
Alternate NamesCode
Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
32. AllergyIntolerance.patient
Definition

The patient who has the allergy or intolerance.

ShortWho the sensitivity is for
Control1..1
TypeReference(US Core Patient Profile)
Is Modifierfalse
Must Supporttrue
Summarytrue
Alternate NamesPatient
Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
34. AllergyIntolerance.encounter
Definition

The encounter when the allergy or intolerance was asserted.

ShortEncounter when the allergy or intolerance was asserted
Control0..1
TypeReference(Encounter)
Is Modifierfalse
Summaryfalse
Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
36. AllergyIntolerance.onset[x]
Definition

Estimated or actual date, date-time, or age when allergy or intolerance was identified.

ShortWhen allergy or intolerance was identified
Control0..1
TypeChoice of: dateTime, Age, Period, Range, string
[x] NoteSee Choice of Data Types for further information about how to use [x]
Is Modifierfalse
Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
Summaryfalse
Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
38. AllergyIntolerance.recordedDate
Definition

The recordedDate represents when this particular AllergyIntolerance record was created in the system, which is often a system-generated date.

ShortDate first version of the resource instance was recorded
Control0..1
TypedateTime
Is Modifierfalse
Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
Summaryfalse
Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
40. AllergyIntolerance.recorder
Definition

Individual who recorded the record and takes responsibility for its content.

ShortWho recorded the sensitivity
Control0..1
TypeReference(Practitioner, PractitionerRole, Patient, RelatedPerson)
Is Modifierfalse
Summaryfalse
Alternate NamesAuthor
Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
42. AllergyIntolerance.asserter
Definition

The source of the information about the allergy that is recorded.

ShortSource of the information about the allergy
Comments

The recorder takes responsibility for the content, but can reference the source from where they got it.

Control0..1
TypeReference(Patient, RelatedPerson, Practitioner, PractitionerRole)
Is Modifierfalse
Summarytrue
Alternate NamesSource, Informant
Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
44. AllergyIntolerance.lastOccurrence
Definition

Represents the date and/or time of the last known occurrence of a reaction event.

ShortDate(/time) of last known occurrence of a reaction
Comments

This date may be replicated by one of the Onset of Reaction dates. Where a textual representation of the date of last occurrence is required e.g. 'In Childhood, '10 years ago' the Comment element should be used.

Control0..1
TypedateTime
Is Modifierfalse
Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
Summaryfalse
Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
46. AllergyIntolerance.note
Definition

Additional narrative about the propensity for the Adverse Reaction, not captured in other fields.

ShortAdditional text not captured in other fields
Comments

For example: including reason for flagging a seriousness of 'High Risk'; and instructions related to future exposure or administration of the substance, such as administration within an Intensive Care Unit or under corticosteroid cover. The notes should be related to an allergy or intolerance as a condition in general and not related to any particular episode of it. For episode notes and descriptions, use AllergyIntolerance.event.description and AllergyIntolerance.event.notes.

Control0..*
TypeAnnotation
Is Modifierfalse
Summaryfalse
Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
48. AllergyIntolerance.reaction
Definition

Details about each adverse reaction event linked to exposure to the identified substance.

ShortAdverse Reaction Events linked to exposure to substance
Control0..*
TypeBackboneElement
Is Modifierfalse
Must Supporttrue
Summaryfalse
Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
50. AllergyIntolerance.reaction.id
Definition

Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces.

ShortUnique id for inter-element referencing
Control0..1
Typestring
Is Modifierfalse
XML FormatIn the XML format, this property is represented as an attribute.
Summaryfalse
52. AllergyIntolerance.reaction.extension
Definition

May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension.

ShortAdditional content defined by implementations
Comments

There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone.

Control0..*
TypeExtension
Is Modifierfalse
Summaryfalse
Alternate Namesextensions, user content
Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
ext-1: Must have either extensions or value[x], not both (extension.exists() != value.exists())
54. AllergyIntolerance.reaction.modifierExtension
Definition

May be used to represent additional information that is not part of the basic definition of the element and that modifies the understanding of the element in which it is contained and/or the understanding of the containing element's descendants. Usually modifier elements provide negation or qualification. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. Applications processing a resource are required to check for modifier extensions.

Modifier extensions SHALL NOT change the meaning of any elements on Resource or DomainResource (including cannot change the meaning of modifierExtension itself).

ShortExtensions that cannot be ignored even if unrecognized
Comments

There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone.

Control0..*
TypeExtension
Is Modifiertrue because Modifier extensions are expected to modify the meaning or interpretation of the element that contains them
Summarytrue
Requirements

Modifier extensions allow for extensions that cannot be safely ignored to be clearly distinguished from the vast majority of extensions which can be safely ignored. This promotes interoperability by eliminating the need for implementers to prohibit the presence of extensions. For further information, see the definition of modifier extensions.

Alternate Namesextensions, user content, modifiers
Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
ext-1: Must have either extensions or value[x], not both (extension.exists() != value.exists())
56. AllergyIntolerance.reaction.substance
Definition

Identification of the specific substance (or pharmaceutical product) considered to be responsible for the Adverse Reaction event. Note: the substance for a specific reaction may be different from the substance identified as the cause of the risk, but it must be consistent with it. For instance, it may be a more specific substance (e.g. a brand medication) or a composite product that includes the identified substance. It must be clinically safe to only process the 'code' and ignore the 'reaction.substance'. If a receiving system is unable to confirm that AllergyIntolerance.reaction.substance falls within the semantic scope of AllergyIntolerance.code, then the receiving system should ignore AllergyIntolerance.reaction.substance.

ShortSpecific substance or pharmaceutical product considered to be responsible for event
Comments

Coding of the specific substance (or pharmaceutical product) with a terminology capable of triggering decision support should be used wherever possible. The 'code' element allows for the use of a specific substance or pharmaceutical product, or a group or class of substances. In the case of an allergy or intolerance to a class of substances, (for example, "penicillins"), the 'reaction.substance' element could be used to code the specific substance that was identified as having caused the reaction (for example, "amoxycillin"). Duplication of the value in the 'code' and 'reaction.substance' elements is acceptable when a specific substance has been recorded in 'code'.

Control0..1
BindingFor example codes, see SubstanceCode
(example to http://hl7.org/fhir/ValueSet/substance-code)

Codes defining the type of the substance (including pharmaceutical products).

TypeCodeableConcept
Is Modifierfalse
Summaryfalse
Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
58. AllergyIntolerance.reaction.manifestation
Definition

Clinical symptoms and/or signs that are observed or associated with the adverse reaction event.

ShortClinical symptoms/signs associated with the Event
Comments

Manifestation can be expressed as a single word, phrase or brief description. For example: nausea, rash or no reaction. It is preferable that manifestation should be coded with a terminology, where possible. The values entered here may be used to display on an application screen as part of a list of adverse reactions, as recommended in the UK NHS CUI guidelines. Terminologies commonly used include, but are not limited to, SNOMED CT or ICD10.

Control1..*
BindingUnless not suitable, these codes SHALL be taken from SNOMEDCTClinicalFindings
(extensible to http://hl7.org/fhir/ValueSet/clinical-findings)
TypeCodeableConcept
Is Modifierfalse
Must Supporttrue
Summaryfalse
Alternate NamesSymptoms, Signs
Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
60. AllergyIntolerance.reaction.description
Definition

Text description about the reaction as a whole, including details of the manifestation if required.

ShortDescription of the event as a whole
Comments

Use the description to provide any details of a particular event of the occurred reaction such as circumstances, reaction specifics, what happened before/after. Information, related to the event, but not describing a particular care should be captured in the comment field. For example: at the age of four, the patient was given penicillin for strep throat and subsequently developed severe hives.

Control0..1
Typestring
Is Modifierfalse
Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
Summaryfalse
Alternate NamesNarrative, Text
Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
62. AllergyIntolerance.reaction.onset
Definition

Record of the date and/or time of the onset of the Reaction.

ShortDate(/time) when manifestations showed
Control0..1
TypedateTime
Is Modifierfalse
Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
Summaryfalse
Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
64. AllergyIntolerance.reaction.severity
Definition

Clinical assessment of the severity of the reaction event as a whole, potentially considering multiple different manifestations.

Shortmild | moderate | severe (of event as a whole)
Comments

It is acknowledged that this assessment is very subjective. There may be some specific practice domains where objective scales have been applied. Objective scales can be included in this model as extensions.

Control0..1
BindingThe codes SHALL be taken from AllergyIntoleranceSeverity
(required to http://hl7.org/fhir/ValueSet/reaction-event-severity|4.0.1)

Clinical assessment of the severity of a reaction event as a whole, potentially considering multiple different manifestations.

Typecode
Is Modifierfalse
Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
Summaryfalse
Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
66. AllergyIntolerance.reaction.exposureRoute
Definition

Identification of the route by which the subject was exposed to the substance.

ShortHow the subject was exposed to the substance
Comments

Coding of the route of exposure with a terminology should be used wherever possible.

Control0..1
BindingFor example codes, see SNOMEDCTRouteCodes
(example to http://hl7.org/fhir/ValueSet/route-codes)

A coded concept describing the route or physiological path of administration of a therapeutic agent into or onto the body of a subject.

TypeCodeableConcept
Is Modifierfalse
Summaryfalse
Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
68. AllergyIntolerance.reaction.note
Definition

Additional text about the adverse reaction event not captured in other fields.

ShortText about event not captured in other fields
Comments

Use this field to record information indirectly related to a particular event and not captured in the description. For example: Clinical records are no longer available, recorded based on information provided to the patient by her mother and her mother is deceased.

Control0..*
TypeAnnotation
Is Modifierfalse
Summaryfalse
Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))