Defines the UK Core constraints and extensions on the AllergyIntolerance resource for the minimal set of data to query and retrieve allergy information.
Profile Purpose
This profile allows a record of a clinical assessment of an allergy or intolerance; a propensity, or a potential risk to an individual, to have an adverse reaction on future exposure to the specified substance, or class of substance.
Where a propensity is identified, to record information or evidence about a reaction event that is characterised by any harmful or undesirable physiological response that is specific to the individual and triggered by exposure of an individual to the identified substance or class of substance.
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.
This resource is used to record physical conditions. It MUST not be used to record preferences for or against types of treatment, for example on religious grounds. For such use cases consider the use of the FHIR Consent resource.
There are no (further) constraints on this element
Element Id
AllergyIntolerance
Short description
Allergy or Intolerance (generally: Risk of adverse reaction to a substance)
Alternate names
Allergy, Intolerance, Adverse Reaction
Definition
Risk of harmful or undesirable, physiological response which is unique to an individual and associated with exposure 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.
dom-2:If the resource is contained in another resource, it SHALL NOT contain nested Resources contained.contained.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-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-6:A resource should have narrative for robust management text.`div`.exists()
dom-5:If a resource is contained in another resource, it SHALL NOT have a security label contained.meta.security.empty()
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()
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.
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.
Supports the date when the allergy or intolerance was no longer valid, and/or, the reason why the allergy or intolerance is no longer valid.
Alternate names
extensions, user content
Definition
Supports the date when the allergy or intolerance was no longer valid, and/or, the reason why the allergy or intolerance is no longer valid.
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.
A reference to results of investigations that confirmed the certainty of the diagnosis.
Alternate names
extensions, user content
Definition
A reference to results of investigations that confirmed the certainty of the diagnosis.
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.
There are no (further) constraints on this element
Element Id
AllergyIntolerance.identifier
Short description
External ids for this item
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.
Requirements
Allows identification of the AllergyIntolerance as it is known by various participating systems and in a way that remains consistent across servers.
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.
ele-1:All FHIR elements must have a @value or children hasValue() or (children().count() > id.count())
Mappings
rim:n/a
v2:CX / EI (occasionally, more often EI maps to a resource id or a URL)
rim:II - The Identifier class is a little looser than the v3 type II because it allows URIs as well as registered OIDs or GUIDs. Also maps to Role[classCode=IDENT]
There are no (further) constraints on this element
Element Id
AllergyIntolerance.identifier.type
Short description
Description of identifier
Definition
A coded type for the identifier that can be used to determine which identifier to use for a specific purpose.
Requirements
Allows users to make use of identifiers when the identifier system is not known.
Comments
This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type.
There are no (further) constraints on this element
Element Id
AllergyIntolerance.identifier.system
Short description
The namespace for the identifier value
Definition
Establishes the namespace for the value - that is, a URL that describes a set values that are unique.
Requirements
There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers.
There are no (further) constraints on this element
Element Id
AllergyIntolerance.identifier.value
Short description
The value that is unique
Definition
The portion of the identifier typically relevant to the user and which is unique within the context of the system.
Comments
If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe.
There are no (further) constraints on this element
Element Id
AllergyIntolerance.identifier.period
Short description
Time period when id is/was valid for use
Definition
Time period during which identifier is/was valid for use.
Comments
A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times").
Period is not used for a duration (a measure of elapsed time). See Duration.
The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization.
ele-1:All FHIR elements must have a @value or children hasValue() or (children().count() > id.count())
ref-1:SHALL have a contained resource if a local reference is provided reference.startsWith('#').not() or (reference.substring(1).trace('url') in %rootResource.contained.id.trace('ids'))
Mappings
rim:n/a
rim:The target of a resource reference is a RIM entry point (Act, Role, or Entity)
v2:CX.4 / (CX.4,CX.9,CX.10)
rim:II.assigningAuthorityName but note that this is an improper use by the definition of the field. Also Role.scoper
There are no (further) constraints on this element
Element Id
AllergyIntolerance.clinicalStatus
Short description
active | inactive | resolved
Definition
The clinical status of the allergy or intolerance.
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.
Assertion about certainty associated with the propensity, or potential risk, of a reaction to the identified substance (including pharmaceutical product).
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.
Identification of the underlying physiological mechanism for the reaction risk.
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.
There are no (further) constraints on this element
Element Id
AllergyIntolerance.category
Short description
food | medication | environment | biologic
Alternate names
Category, Type, Reaction Type, Class
Definition
Category of the identified substance.
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.
There are no (further) constraints on this element
Element Id
AllergyIntolerance.criticality
Short description
low | high | unable-to-assess
Alternate names
Severity, Seriousness, Contra-indication, Risk
Definition
Estimate of the potential clinical harm, or seriousness, of the reaction to the identified substance.
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.
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.
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.
References SHALL be a reference to an actual FHIR resource, and SHALL be resolveable (allowing for access control, temporary unavailability, etc.). Resolution can be either by retrieval from the URL, or, where applicable by resource type, by treating an absolute reference as a canonical URL and looking it up in a local registry/repository.
ele-1:All FHIR elements must have a @value or children hasValue() or (children().count() > id.count())
ref-1:SHALL have a contained resource if a local reference is provided reference.startsWith('#').not() or (reference.substring(1).trace('url') in %rootResource.contained.id.trace('ids'))
Mappings
rim:n/a
rim:The target of a resource reference is a RIM entry point (Act, Role, or Entity)
Encounter when the allergy or intolerance was asserted
Definition
The encounter when the allergy or intolerance was asserted.
Comments
References SHALL be a reference to an actual FHIR resource, and SHALL be resolveable (allowing for access control, temporary unavailability, etc.). Resolution can be either by retrieval from the URL, or, where applicable by resource type, by treating an absolute reference as a canonical URL and looking it up in a local registry/repository.
ele-1:All FHIR elements must have a @value or children hasValue() or (children().count() > id.count())
ref-1:SHALL have a contained resource if a local reference is provided reference.startsWith('#').not() or (reference.substring(1).trace('url') in %rootResource.contained.id.trace('ids'))
Mappings
rim:n/a
rim:The target of a resource reference is a RIM entry point (Act, Role, or Entity)
Individual who recorded the record and takes responsibility for its content.
Comments
References SHALL be a reference to an actual FHIR resource, and SHALL be resolveable (allowing for access control, temporary unavailability, etc.). Resolution can be either by retrieval from the URL, or, where applicable by resource type, by treating an absolute reference as a canonical URL and looking it up in a local registry/repository.
ele-1:All FHIR elements must have a @value or children hasValue() or (children().count() > id.count())
ref-1:SHALL have a contained resource if a local reference is provided reference.startsWith('#').not() or (reference.substring(1).trace('url') in %rootResource.contained.id.trace('ids'))
Mappings
rim:n/a
rim:The target of a resource reference is a RIM entry point (Act, Role, or Entity)
ele-1:All FHIR elements must have a @value or children hasValue() or (children().count() > id.count())
ref-1:SHALL have a contained resource if a local reference is provided reference.startsWith('#').not() or (reference.substring(1).trace('url') in %rootResource.contained.id.trace('ids'))
Mappings
rim:n/a
rim:The target of a resource reference is a RIM entry point (Act, Role, or Entity)
There are no (further) constraints on this element
Element Id
AllergyIntolerance.lastOccurrence
Short description
Date(/time) of last known occurrence of a reaction
Definition
Represents the date and/or time of the last known occurrence of a reaction event.
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.
There are no (further) constraints on this element
Element Id
AllergyIntolerance.note
Short description
Additional text not captured in other fields
Definition
Additional narrative about the propensity for the Adverse Reaction, 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.
There are no (further) constraints on this element
Element Id
AllergyIntolerance.note.text
Short description
The annotation - text content (as markdown)
Definition
The text of the annotation in markdown format.
Comments
Systems are not required to have markdown support, so the text should be readable without markdown processing. The markdown syntax is GFM - see https://github.github.com/gfm/
Specific substance or pharmaceutical product considered to be responsible for event
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.
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'.
Clinical symptoms and/or signs that are observed or associated with the adverse reaction 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.
There are no (further) constraints on this element
Element Id
AllergyIntolerance.reaction.description
Short description
Description of the event as a whole
Alternate names
Narrative, Text
Definition
Text description about the reaction as a whole, including details of the manifestation if required.
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.
There are no (further) constraints on this element
Element Id
AllergyIntolerance.reaction.severity
Short description
mild | moderate | severe (of event as a whole)
Definition
Clinical assessment of the severity of the reaction event as a whole, potentially considering multiple different manifestations.
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.
There are no (further) constraints on this element
Element Id
AllergyIntolerance.reaction.note
Short description
Text about event not captured in other fields
Definition
Additional text about the adverse reaction 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.
There are no (further) constraints on this element
Element Id
AllergyIntolerance.reaction.note.text
Short description
The annotation - text content (as markdown)
Definition
The text of the annotation in markdown format.
Comments
Systems are not required to have markdown support, so the text should be readable without markdown processing. The markdown syntax is GFM - see https://github.github.com/gfm/
There are no (further) constraints on this element
Element Id
AllergyIntolerance
Short description
Allergy or Intolerance (generally: Risk of adverse reaction to a substance)
Alternate names
Allergy, Intolerance, Adverse Reaction
Definition
Risk of harmful or undesirable, physiological response which is unique to an individual and associated with exposure 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.
dom-2:If the resource is contained in another resource, it SHALL NOT contain nested Resources contained.contained.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-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-6:A resource should have narrative for robust management text.`div`.exists()
dom-5:If a resource is contained in another resource, it SHALL NOT have a security label contained.meta.security.empty()
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()
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.
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.
Supports the date when the allergy or intolerance was no longer valid, and/or, the reason why the allergy or intolerance is no longer valid.
Alternate names
extensions, user content
Definition
Supports the date when the allergy or intolerance was no longer valid, and/or, the reason why the allergy or intolerance is no longer valid.
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.
A reference to results of investigations that confirmed the certainty of the diagnosis.
Alternate names
extensions, user content
Definition
A reference to results of investigations that confirmed the certainty of the diagnosis.
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.
There are no (further) constraints on this element
Element Id
AllergyIntolerance.identifier
Short description
External ids for this item
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.
Requirements
Allows identification of the AllergyIntolerance as it is known by various participating systems and in a way that remains consistent across servers.
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.
ele-1:All FHIR elements must have a @value or children hasValue() or (children().count() > id.count())
Mappings
rim:n/a
v2:CX / EI (occasionally, more often EI maps to a resource id or a URL)
rim:II - The Identifier class is a little looser than the v3 type II because it allows URIs as well as registered OIDs or GUIDs. Also maps to Role[classCode=IDENT]
There are no (further) constraints on this element
Element Id
AllergyIntolerance.identifier.type
Short description
Description of identifier
Definition
A coded type for the identifier that can be used to determine which identifier to use for a specific purpose.
Requirements
Allows users to make use of identifiers when the identifier system is not known.
Comments
This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type.
There are no (further) constraints on this element
Element Id
AllergyIntolerance.identifier.system
Short description
The namespace for the identifier value
Definition
Establishes the namespace for the value - that is, a URL that describes a set values that are unique.
Requirements
There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers.
There are no (further) constraints on this element
Element Id
AllergyIntolerance.identifier.value
Short description
The value that is unique
Definition
The portion of the identifier typically relevant to the user and which is unique within the context of the system.
Comments
If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe.
There are no (further) constraints on this element
Element Id
AllergyIntolerance.identifier.period
Short description
Time period when id is/was valid for use
Definition
Time period during which identifier is/was valid for use.
Comments
A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times").
Period is not used for a duration (a measure of elapsed time). See Duration.
The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization.
ele-1:All FHIR elements must have a @value or children hasValue() or (children().count() > id.count())
ref-1:SHALL have a contained resource if a local reference is provided reference.startsWith('#').not() or (reference.substring(1).trace('url') in %rootResource.contained.id.trace('ids'))
Mappings
rim:n/a
rim:The target of a resource reference is a RIM entry point (Act, Role, or Entity)
v2:CX.4 / (CX.4,CX.9,CX.10)
rim:II.assigningAuthorityName but note that this is an improper use by the definition of the field. Also Role.scoper
There are no (further) constraints on this element
Element Id
AllergyIntolerance.clinicalStatus
Short description
active | inactive | resolved
Definition
The clinical status of the allergy or intolerance.
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.
Assertion about certainty associated with the propensity, or potential risk, of a reaction to the identified substance (including pharmaceutical product).
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.
Identification of the underlying physiological mechanism for the reaction risk.
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.
There are no (further) constraints on this element
Element Id
AllergyIntolerance.category
Short description
food | medication | environment | biologic
Alternate names
Category, Type, Reaction Type, Class
Definition
Category of the identified substance.
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.
There are no (further) constraints on this element
Element Id
AllergyIntolerance.criticality
Short description
low | high | unable-to-assess
Alternate names
Severity, Seriousness, Contra-indication, Risk
Definition
Estimate of the potential clinical harm, or seriousness, of the reaction to the identified substance.
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.
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.
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.
References SHALL be a reference to an actual FHIR resource, and SHALL be resolveable (allowing for access control, temporary unavailability, etc.). Resolution can be either by retrieval from the URL, or, where applicable by resource type, by treating an absolute reference as a canonical URL and looking it up in a local registry/repository.
ele-1:All FHIR elements must have a @value or children hasValue() or (children().count() > id.count())
ref-1:SHALL have a contained resource if a local reference is provided reference.startsWith('#').not() or (reference.substring(1).trace('url') in %rootResource.contained.id.trace('ids'))
Mappings
rim:n/a
rim:The target of a resource reference is a RIM entry point (Act, Role, or Entity)
Encounter when the allergy or intolerance was asserted
Definition
The encounter when the allergy or intolerance was asserted.
Comments
References SHALL be a reference to an actual FHIR resource, and SHALL be resolveable (allowing for access control, temporary unavailability, etc.). Resolution can be either by retrieval from the URL, or, where applicable by resource type, by treating an absolute reference as a canonical URL and looking it up in a local registry/repository.
ele-1:All FHIR elements must have a @value or children hasValue() or (children().count() > id.count())
ref-1:SHALL have a contained resource if a local reference is provided reference.startsWith('#').not() or (reference.substring(1).trace('url') in %rootResource.contained.id.trace('ids'))
Mappings
rim:n/a
rim:The target of a resource reference is a RIM entry point (Act, Role, or Entity)
Individual who recorded the record and takes responsibility for its content.
Comments
References SHALL be a reference to an actual FHIR resource, and SHALL be resolveable (allowing for access control, temporary unavailability, etc.). Resolution can be either by retrieval from the URL, or, where applicable by resource type, by treating an absolute reference as a canonical URL and looking it up in a local registry/repository.
ele-1:All FHIR elements must have a @value or children hasValue() or (children().count() > id.count())
ref-1:SHALL have a contained resource if a local reference is provided reference.startsWith('#').not() or (reference.substring(1).trace('url') in %rootResource.contained.id.trace('ids'))
Mappings
rim:n/a
rim:The target of a resource reference is a RIM entry point (Act, Role, or Entity)
ele-1:All FHIR elements must have a @value or children hasValue() or (children().count() > id.count())
ref-1:SHALL have a contained resource if a local reference is provided reference.startsWith('#').not() or (reference.substring(1).trace('url') in %rootResource.contained.id.trace('ids'))
Mappings
rim:n/a
rim:The target of a resource reference is a RIM entry point (Act, Role, or Entity)
There are no (further) constraints on this element
Element Id
AllergyIntolerance.lastOccurrence
Short description
Date(/time) of last known occurrence of a reaction
Definition
Represents the date and/or time of the last known occurrence of a reaction event.
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.
There are no (further) constraints on this element
Element Id
AllergyIntolerance.note
Short description
Additional text not captured in other fields
Definition
Additional narrative about the propensity for the Adverse Reaction, 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.
There are no (further) constraints on this element
Element Id
AllergyIntolerance.note.text
Short description
The annotation - text content (as markdown)
Definition
The text of the annotation in markdown format.
Comments
Systems are not required to have markdown support, so the text should be readable without markdown processing. The markdown syntax is GFM - see https://github.github.com/gfm/
Specific substance or pharmaceutical product considered to be responsible for event
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.
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'.
Clinical symptoms and/or signs that are observed or associated with the adverse reaction 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.
There are no (further) constraints on this element
Element Id
AllergyIntolerance.reaction.description
Short description
Description of the event as a whole
Alternate names
Narrative, Text
Definition
Text description about the reaction as a whole, including details of the manifestation if required.
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.
There are no (further) constraints on this element
Element Id
AllergyIntolerance.reaction.severity
Short description
mild | moderate | severe (of event as a whole)
Definition
Clinical assessment of the severity of the reaction event as a whole, potentially considering multiple different manifestations.
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.
There are no (further) constraints on this element
Element Id
AllergyIntolerance.reaction.note
Short description
Text about event not captured in other fields
Definition
Additional text about the adverse reaction 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.
There are no (further) constraints on this element
Element Id
AllergyIntolerance.reaction.note.text
Short description
The annotation - text content (as markdown)
Definition
The text of the annotation in markdown format.
Comments
Systems are not required to have markdown support, so the text should be readable without markdown processing. The markdown syntax is GFM - see https://github.github.com/gfm/
There are no (further) constraints on this element
Element Id
AllergyIntolerance
Short description
Allergy or Intolerance (generally: Risk of adverse reaction to a substance)
Alternate names
Allergy, Intolerance, Adverse Reaction
Definition
Risk of harmful or undesirable, physiological response which is unique to an individual and associated with exposure 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.
dom-2:If the resource is contained in another resource, it SHALL NOT contain nested Resources contained.contained.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-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-6:A resource should have narrative for robust management text.`div`.exists()
dom-5:If a resource is contained in another resource, it SHALL NOT have a security label contained.meta.security.empty()
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()
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.
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.
Supports the date when the allergy or intolerance was no longer valid, and/or, the reason why the allergy or intolerance is no longer valid.
Alternate names
extensions, user content
Definition
Supports the date when the allergy or intolerance was no longer valid, and/or, the reason why the allergy or intolerance is no longer valid.
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.
A reference to results of investigations that confirmed the certainty of the diagnosis.
Alternate names
extensions, user content
Definition
A reference to results of investigations that confirmed the certainty of the diagnosis.
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.
There are no (further) constraints on this element
Element Id
AllergyIntolerance.identifier
Short description
External ids for this item
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.
Requirements
Allows identification of the AllergyIntolerance as it is known by various participating systems and in a way that remains consistent across servers.
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.
ele-1:All FHIR elements must have a @value or children hasValue() or (children().count() > id.count())
Mappings
rim:n/a
v2:CX / EI (occasionally, more often EI maps to a resource id or a URL)
rim:II - The Identifier class is a little looser than the v3 type II because it allows URIs as well as registered OIDs or GUIDs. Also maps to Role[classCode=IDENT]
There are no (further) constraints on this element
Element Id
AllergyIntolerance.identifier.type
Short description
Description of identifier
Definition
A coded type for the identifier that can be used to determine which identifier to use for a specific purpose.
Requirements
Allows users to make use of identifiers when the identifier system is not known.
Comments
This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type.
There are no (further) constraints on this element
Element Id
AllergyIntolerance.identifier.system
Short description
The namespace for the identifier value
Definition
Establishes the namespace for the value - that is, a URL that describes a set values that are unique.
Requirements
There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers.
There are no (further) constraints on this element
Element Id
AllergyIntolerance.identifier.value
Short description
The value that is unique
Definition
The portion of the identifier typically relevant to the user and which is unique within the context of the system.
Comments
If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe.
There are no (further) constraints on this element
Element Id
AllergyIntolerance.identifier.period
Short description
Time period when id is/was valid for use
Definition
Time period during which identifier is/was valid for use.
Comments
A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times").
Period is not used for a duration (a measure of elapsed time). See Duration.
The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization.
ele-1:All FHIR elements must have a @value or children hasValue() or (children().count() > id.count())
ref-1:SHALL have a contained resource if a local reference is provided reference.startsWith('#').not() or (reference.substring(1).trace('url') in %rootResource.contained.id.trace('ids'))
Mappings
rim:n/a
rim:The target of a resource reference is a RIM entry point (Act, Role, or Entity)
v2:CX.4 / (CX.4,CX.9,CX.10)
rim:II.assigningAuthorityName but note that this is an improper use by the definition of the field. Also Role.scoper
There are no (further) constraints on this element
Element Id
AllergyIntolerance.clinicalStatus
Short description
active | inactive | resolved
Definition
The clinical status of the allergy or intolerance.
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.
Assertion about certainty associated with the propensity, or potential risk, of a reaction to the identified substance (including pharmaceutical product).
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.
Identification of the underlying physiological mechanism for the reaction risk.
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.
There are no (further) constraints on this element
Element Id
AllergyIntolerance.category
Short description
food | medication | environment | biologic
Alternate names
Category, Type, Reaction Type, Class
Definition
Category of the identified substance.
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.
There are no (further) constraints on this element
Element Id
AllergyIntolerance.criticality
Short description
low | high | unable-to-assess
Alternate names
Severity, Seriousness, Contra-indication, Risk
Definition
Estimate of the potential clinical harm, or seriousness, of the reaction to the identified substance.
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.
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.
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.
References SHALL be a reference to an actual FHIR resource, and SHALL be resolveable (allowing for access control, temporary unavailability, etc.). Resolution can be either by retrieval from the URL, or, where applicable by resource type, by treating an absolute reference as a canonical URL and looking it up in a local registry/repository.
ele-1:All FHIR elements must have a @value or children hasValue() or (children().count() > id.count())
ref-1:SHALL have a contained resource if a local reference is provided reference.startsWith('#').not() or (reference.substring(1).trace('url') in %rootResource.contained.id.trace('ids'))
Mappings
rim:n/a
rim:The target of a resource reference is a RIM entry point (Act, Role, or Entity)
Encounter when the allergy or intolerance was asserted
Definition
The encounter when the allergy or intolerance was asserted.
Comments
References SHALL be a reference to an actual FHIR resource, and SHALL be resolveable (allowing for access control, temporary unavailability, etc.). Resolution can be either by retrieval from the URL, or, where applicable by resource type, by treating an absolute reference as a canonical URL and looking it up in a local registry/repository.
ele-1:All FHIR elements must have a @value or children hasValue() or (children().count() > id.count())
ref-1:SHALL have a contained resource if a local reference is provided reference.startsWith('#').not() or (reference.substring(1).trace('url') in %rootResource.contained.id.trace('ids'))
Mappings
rim:n/a
rim:The target of a resource reference is a RIM entry point (Act, Role, or Entity)
Individual who recorded the record and takes responsibility for its content.
Comments
References SHALL be a reference to an actual FHIR resource, and SHALL be resolveable (allowing for access control, temporary unavailability, etc.). Resolution can be either by retrieval from the URL, or, where applicable by resource type, by treating an absolute reference as a canonical URL and looking it up in a local registry/repository.
ele-1:All FHIR elements must have a @value or children hasValue() or (children().count() > id.count())
ref-1:SHALL have a contained resource if a local reference is provided reference.startsWith('#').not() or (reference.substring(1).trace('url') in %rootResource.contained.id.trace('ids'))
Mappings
rim:n/a
rim:The target of a resource reference is a RIM entry point (Act, Role, or Entity)
ele-1:All FHIR elements must have a @value or children hasValue() or (children().count() > id.count())
ref-1:SHALL have a contained resource if a local reference is provided reference.startsWith('#').not() or (reference.substring(1).trace('url') in %rootResource.contained.id.trace('ids'))
Mappings
rim:n/a
rim:The target of a resource reference is a RIM entry point (Act, Role, or Entity)
There are no (further) constraints on this element
Element Id
AllergyIntolerance.lastOccurrence
Short description
Date(/time) of last known occurrence of a reaction
Definition
Represents the date and/or time of the last known occurrence of a reaction event.
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.
There are no (further) constraints on this element
Element Id
AllergyIntolerance.note
Short description
Additional text not captured in other fields
Definition
Additional narrative about the propensity for the Adverse Reaction, 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.
There are no (further) constraints on this element
Element Id
AllergyIntolerance.note.text
Short description
The annotation - text content (as markdown)
Definition
The text of the annotation in markdown format.
Comments
Systems are not required to have markdown support, so the text should be readable without markdown processing. The markdown syntax is GFM - see https://github.github.com/gfm/
Specific substance or pharmaceutical product considered to be responsible for event
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.
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'.
Clinical symptoms and/or signs that are observed or associated with the adverse reaction 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.
There are no (further) constraints on this element
Element Id
AllergyIntolerance.reaction.description
Short description
Description of the event as a whole
Alternate names
Narrative, Text
Definition
Text description about the reaction as a whole, including details of the manifestation if required.
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.
There are no (further) constraints on this element
Element Id
AllergyIntolerance.reaction.severity
Short description
mild | moderate | severe (of event as a whole)
Definition
Clinical assessment of the severity of the reaction event as a whole, potentially considering multiple different manifestations.
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.
There are no (further) constraints on this element
Element Id
AllergyIntolerance.reaction.note
Short description
Text about event not captured in other fields
Definition
Additional text about the adverse reaction 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.
There are no (further) constraints on this element
Element Id
AllergyIntolerance.reaction.note.text
Short description
The annotation - text content (as markdown)
Definition
The text of the annotation in markdown format.
Comments
Systems are not required to have markdown support, so the text should be readable without markdown processing. The markdown syntax is GFM - see https://github.github.com/gfm/
<StructureDefinitionxmlns="http://hl7.org/fhir"><idvalue="UKCore-AllergyIntolerance" /><urlvalue="https://fhir.hl7.org.uk/StructureDefinition/UKCore-AllergyIntolerance" /><versionvalue="2.1.0" /><namevalue="UKCoreAllergyIntolerance" /><titlevalue="UK Core AllergyIntolerance" /><statusvalue="active" /><datevalue="2021-09-10" /><publishervalue="HL7 UK" /><contact><namevalue="HL7 UK" /><telecom><systemvalue="email" /><valuevalue="secretariat@hl7.org.uk" /><usevalue="work" /><rankvalue="1" /></telecom></contact><contact><namevalue="NHS Digital" /><telecom><systemvalue="email" /><valuevalue="interoperabilityteam@nhs.net" /><usevalue="work" /><rankvalue="2" /></telecom></contact><descriptionvalue="Defines the UK Core constraints and extensions on the AllergyIntolerance resource for the minimal set of data to query and retrieve allergy information." /><purposevalue="This profile allows a record of a clinical assessment of an allergy or intolerance; a propensity, or a potential risk to an individual, to have an adverse reaction on future exposure to the specified substance, or class of substance. \nWhere a propensity is identified, to record information or evidence about a reaction event that is characterised by any harmful or undesirable physiological response that is specific to the individual and triggered by exposure of an individual to the identified substance or class of substance. \nSubstances 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." /><copyrightvalue="Copyright © 2021+ HL7 UK Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at http://www.apache.org/licenses/LICENSE-2.0 Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License. HL7® FHIR® standard Copyright © 2011+ HL7 The HL7® FHIR® standard is used under the FHIR license. You may obtain a copy of the FHIR license at https://www.hl7.org/fhir/license.html." /><fhirVersionvalue="4.0.1" /><mapping><identityvalue="rim" /><urivalue="http://hl7.org/v3" /><namevalue="RIM Mapping" /></mapping><mapping><identityvalue="w5" /><urivalue="http://hl7.org/fhir/fivews" /><namevalue="FiveWs Pattern Mapping" /></mapping><mapping><identityvalue="v2" /><urivalue="http://hl7.org/v2" /><namevalue="HL7 v2 Mapping" /></mapping><kindvalue="resource" /><abstractvalue="false" /><typevalue="AllergyIntolerance" /><baseDefinitionvalue="http://hl7.org/fhir/StructureDefinition/AllergyIntolerance" /><derivationvalue="constraint" /><differential><elementid="AllergyIntolerance.extension"><pathvalue="AllergyIntolerance.extension" /><slicing><discriminator><typevalue="value" /><pathvalue="url" /></discriminator><rulesvalue="open" /></slicing></element><elementid="AllergyIntolerance.extension:allergyIntoleranceEnd"><pathvalue="AllergyIntolerance.extension" /><sliceNamevalue="allergyIntoleranceEnd" /><type><codevalue="Extension" /><profilevalue="https://fhir.hl7.org.uk/StructureDefinition/Extension-UKCore-AllergyIntoleranceEnd" /></type></element><elementid="AllergyIntolerance.extension:evidence"><pathvalue="AllergyIntolerance.extension" /><sliceNamevalue="evidence" /><shortvalue="A reference to results of investigations that confirmed the certainty of the diagnosis." /><type><codevalue="Extension" /><profilevalue="https://fhir.hl7.org.uk/StructureDefinition/Extension-UKCore-Evidence" /></type></element><elementid="AllergyIntolerance.identifier.assigner"><pathvalue="AllergyIntolerance.identifier.assigner" /><type><codevalue="Reference" /><targetProfilevalue="https://fhir.hl7.org.uk/StructureDefinition/UKCore-Organization" /></type></element><elementid="AllergyIntolerance.code"><pathvalue="AllergyIntolerance.code" /><minvalue="1" /><binding><strengthvalue="extensible" /><valueSetvalue="https://fhir.hl7.org.uk/ValueSet/UKCore-AllergyCode" /></binding></element><elementid="AllergyIntolerance.patient"><pathvalue="AllergyIntolerance.patient" /><type><codevalue="Reference" /><targetProfilevalue="https://fhir.hl7.org.uk/StructureDefinition/UKCore-Patient" /></type></element><elementid="AllergyIntolerance.encounter"><pathvalue="AllergyIntolerance.encounter" /><type><codevalue="Reference" /><targetProfilevalue="https://fhir.hl7.org.uk/StructureDefinition/UKCore-Encounter" /></type></element><elementid="AllergyIntolerance.recorder"><pathvalue="AllergyIntolerance.recorder" /><type><codevalue="Reference" /><targetProfilevalue="https://fhir.hl7.org.uk/StructureDefinition/UKCore-Practitioner" /><targetProfilevalue="https://fhir.hl7.org.uk/StructureDefinition/UKCore-PractitionerRole" /><targetProfilevalue="https://fhir.hl7.org.uk/StructureDefinition/UKCore-Patient" /><targetProfilevalue="https://fhir.hl7.org.uk/StructureDefinition/UKCore-RelatedPerson" /></type></element><elementid="AllergyIntolerance.asserter"><pathvalue="AllergyIntolerance.asserter" /><type><codevalue="Reference" /><targetProfilevalue="https://fhir.hl7.org.uk/StructureDefinition/UKCore-Patient" /><targetProfilevalue="https://fhir.hl7.org.uk/StructureDefinition/UKCore-RelatedPerson" /><targetProfilevalue="https://fhir.hl7.org.uk/StructureDefinition/UKCore-Practitioner" /><targetProfilevalue="https://fhir.hl7.org.uk/StructureDefinition/UKCore-PractitionerRole" /></type></element><elementid="AllergyIntolerance.note.author[x]"><pathvalue="AllergyIntolerance.note.author[x]" /><type><codevalue="Reference" /><targetProfilevalue="https://fhir.hl7.org.uk/StructureDefinition/UKCore-Practitioner" /><targetProfilevalue="https://fhir.hl7.org.uk/StructureDefinition/UKCore-Patient" /><targetProfilevalue="https://fhir.hl7.org.uk/StructureDefinition/UKCore-RelatedPerson" /><targetProfilevalue="https://fhir.hl7.org.uk/StructureDefinition/UKCore-Organization" /></type><type><codevalue="string" /></type></element><elementid="AllergyIntolerance.reaction.substance"><pathvalue="AllergyIntolerance.reaction.substance" /><binding><strengthvalue="extensible" /><valueSetvalue="https://fhir.hl7.org.uk/ValueSet/UKCore-AllergySubstance" /></binding></element><elementid="AllergyIntolerance.reaction.manifestation"><pathvalue="AllergyIntolerance.reaction.manifestation" /><binding><strengthvalue="extensible" /><valueSetvalue="https://fhir.hl7.org.uk/ValueSet/UKCore-AllergyManifestation" /></binding></element><elementid="AllergyIntolerance.reaction.exposureRoute"><pathvalue="AllergyIntolerance.reaction.exposureRoute" /><binding><strengthvalue="extensible" /><valueSetvalue="https://fhir.hl7.org.uk/ValueSet/UKCore-SubstanceOrProductAdministrationRoute" /></binding></element><elementid="AllergyIntolerance.reaction.note.author[x]"><pathvalue="AllergyIntolerance.reaction.note.author[x]" /><type><codevalue="Reference" /><targetProfilevalue="https://fhir.hl7.org.uk/StructureDefinition/UKCore-Practitioner" /><targetProfilevalue="https://fhir.hl7.org.uk/StructureDefinition/UKCore-Patient" /><targetProfilevalue="https://fhir.hl7.org.uk/StructureDefinition/UKCore-RelatedPerson" /><targetProfilevalue="https://fhir.hl7.org.uk/StructureDefinition/UKCore-Organization" /></type><type><codevalue="string" /></type></element></differential></StructureDefinition>
Example UKCore-AllergyIntolerance-Evidence to reference a DiagnosticReport resource for investigations that confirm the certainty of the allergy or intolerance diagnosis.
identifier
The identifier is the most important element of a FHIR resource for interoperability. It acts as the externally facing unique business identifier for the resource. A key phrase from the FHIR R4 standard is;
[for identifier] ...All resources that have an identifier element support searching by the identifier, so that records can be located by that method.
Provider Systems
It is recommended that the identifier value is a Universally Unique Identifier (UUID) as there is no nationally recognised business indentier for an instance of a recorded allergy or intolerence.
Consumer Systems
Consumer systems MUST consume this data.
clinicalStatus
A value from a required terminology binding containing the values;
active
inactive
resolved.
The FHIR standard states this element SHALL be present if verificationStatus is notentered-in-error, but SHALL NOT be present if verificationStatus is entered-in-error.
Provider Systems
Provider systems MUST provide this data.
Consumer Systems
Consumer systems MUST consume this data.
Handling changes in clinical status
A recorded allergy may be subsequently proven to have a different clinical status, e.g. from active to inactive. In this scenario provider systems should create a new instance of this resource to reflect the change of clinical status.
This is opposed to updating the existing instance of the resource. This resource has no data element that could convey a last updated date. Also the action of updating the resource may not be picked up by consumer systems. Creating a new instance of the resource is the safer implementation approach.
verificationStatus
An optional value from a required terminology binding containing the values;
unconfirmed
confirmed
refuted
entered-in-error.
Note that the use of entered-in-error dictates the population of the clinicalStatus element.
Provider Systems
This element is optional.
Consumer Systems
If omitted, a verification status akin to confirmed should be assumed.
type
An optional value from a required terminology binding containing the values;
allergy
intolerance.
Provider Systems
It is recommended to omit this element. There are no confirmed use cases where clinical system functionality or logic would change based on this data. There are no confirmed use cases where the clinical practitioner would change a care plan based on this data.
Consumer Systems
This element can be ignored.
category
An optional value from a required terminology binding containing the values;
food
medication
environment
biologic.
Provider Systems
It is recommended to omit this element. There are no confirmed use cases where clinical system functionality or logic would change based on this data. There are no confirmed use cases where the clinical practitioner would change a care plan based on this data.
Consumer Systems
This element can be ignored.
criticality
An optional value from a required terminology binding containing the values;
low
high
unable-to-assess,
Use of this element when populated as high may be used to express life threatening allergies, used in conjunction with the AllergyIntolerance.reaction.severity element.
Provider Systems
This element is optional.
Consumer Systems
If omitted, a criticality akin to low should be assumed.
code (Mandatory)
Identifies the causative agent for the allergy or intolerance.
When recording an allergy to a medication substance, the provider system should use a dm+d concept class.
National Health Service dictionary of medicines and devices combination drug Virtual Therapeutic Moiety (VTM) – just the drugs, no formulation. May be additional concepts to those in SNOMED-CT (SCT) hierarchy.
National Health Service dictionary of medicines and devices Virtual Medicinal Product (VMP) - generic drug products and also generic appliance/ device concepts. May be additional concepts to those in SCT hierarchy and will support the recording of allergies to bandages and dressings etc. Device/appliances are concepts that would not be within scope of SCT pharmaceutical/biologic product hierarchy.
National Health Service dictionary of medicines and devices Actual Medicinal Product (AMP) – branded drug products and branded appliance/device concepts that would not be within scope of SCT pharmaceutical/ biologic product hierarchy.
National Health Service dictionary of medicines and devices ingredient – just the drug ingredients, no formulation. May be additional concepts to those in SCT hierarchy. Important to have this in addition to VTM as some things may be more specific at VTM level for example things only available as combinations where VTM would only be the combination also VTM may not identify the salt but this concept class would support that.
Alternatively, or when the allergy is not recorded against a medication substance, the relevant set of SNOMED CT codes is a union of the following.
Note: “Septrin” is a long discontinued brand name of an antibiotic.
If a pre-coordinated allergy code is known which this is not part of the permitted value set for causative agent defined above.
XML
<code><coding><systemvalue="http://snomed.info/sct"/><codevalue="196461000000101"/><displayvalue="transfer-degraded drug allergy (record artifact)"/></coding><textvalue="213020009 | Allergy to egg protein"/></code>
The representation of the causative agent as text is supported within the FHIR standard but this should only be used as a last resort if a suitable coded term does not exist within the SNOMED-CT terminology or if using a degraded allergy code is not appropriate.
Use of nullFlavor
The UK Core recommendation is that the nullFlavor is not used for the causative agent, even though it is permitted within the FHIR standard.
Provider Systems
Provider systems MUST provide this data.
Consumer Systems
Consumer systems MUST consume this data.
patient (Mandatory)
A reference to the patient.
Provider Systems
Provider systems MUST provide this data.
Within a FHIR Messaging or FHIR Document implementation, include a UKCore-Patient resource within the Bundle with at least the minimum dataset populated as defined within the UK Core standard. The reference points to the resource in the Bundle.
XML
<!-- within the AllergyIntolernce resource...--><patient><referencevalue="urn:patient-011223344"/><displayvalue="Richard Smith"/></patient><!-- elsewhere in the Bundle...--><Patient><idvalue="urn:patient-011223344"/><identifier><systemvalue="https://fhir.nhs.uk/Id/nhs-number"/><valuevalue="9912003888"/></identifier><name><usevalue="official"/><textvalue="Mr Richard Smith"/>
<family value="Smith/>
<given value="Richard/>
<prefixvalue="Mr"/></name><gendervalue="male"/><birthDatevalue="1956-02-04"/>>
</Patient>
Within a RESTful implemementation a reference and/or identifierMUST be provided that allows the consumer system to query another API if they need to access the complete UKCore-Patient resource. The reference points to the resource in the Bundle.
For implementations within England and Wales, the identifier could be the patient's NHS Number, allowing consumer system to use the NHS Digital Personal Demographics Service FHIR API return a Patient resource.
Implementation guidance is pending further analysis for the potential use of this element.
onset[x]
Record of the date and/or time of the onset of the reaction caused by the allergy or intolerance which can be recorded in one of five ways;
onsetDateTime
onsetAge
onsetPeriod
onsetRange
onsetString.
Provider Systems
Provider systems are recommended to support at least onsetDateTime and onsetAge where this date is available.
It is recommended not to record the onset using an onsetPeriod or onsetRange as these data types are complex and less useful. If the exact onset date is not known, but was between two known dates, e.g. 2018 and 2019, then use the lower/older date as the onsetDateTime instead of using an onsetPeriod.
It is recommended not to record the onset using an onsetString as this data will not be machine processable.
Consumer Systems
Consumer systems MUST be able to handle any of the onset data types.
recordedDate
The date the first version of the resource instance was recorded.
The recordedDate represents when this particular AllergyIntolerance record was created in the system, which is often a system-generated date.
If the instance of the resource is updated via an operation like a RESTful PATCH or PUT then the recordedDate is not updated and remains the date the resource instance was recorded.
Provider Systems
Provider systems MUST provide this data.
Consumer Systems
Consumer systems MUST consume this data.
recorder
Individual who recorded the record and takes responsibility for its content.
Provider Systems
Provider systems should provide this data.
Consumer Systems
Consumer systems should consume this data.
asserter
The source of the information about the allergy. A reference to patient, relatedPerson, practitioner or practitionerRole resource.
Provider Systems
Provider systems should provide at least the following minimum data within the referenced resource.
practioner
identifier
name
practionerRole
identifier
practitioner (as above) OR organisation.identifier OR healthcareService.identifier
patient
identifier:nhsNumber
name
relatedPerson
identifier
name
patient
Where a human asserter is not captured or cannot be confirmed, i.e. a practioner, patient or relatedPerson, the provider systems should reference an Organisation and/or healthcareService within a PractitonerRole, using the associated ODS code.
For example, asserted by "MILTON KEYNES UNIVERSITY HOSPITAL NHS FOUNDATION TRUST".
XML
<PractitionerRole><identifier><valuevalue="7d107ed2-70c6-43d9-9cbe-f19c319d1456"/><organization><identifier><systemvalue="https://fhir.nhs.uk/Id/ods-organization-code"/><valuevalue="RD8"/></identifier><displayvalue="MILTON KEYNES UNIVERSITY HOSPITAL NHS FOUNDATION TRUST"/></organization></PractitionerRole>
Represents the date and/or time of the last known occurrence of a reaction event.
Provider Systems
Provider systems should populate with the date or date/time of the last known occurrence of a reaction to the allergy, if known.
Consumer Systems
Consumer systems may choose to consume this data.
note
An optional element for when the clinical user wishes to provides supporting textual information for the allergy record that cannot be conveyed within other elements of the resource.
Provider Systems
Where a provider system only has the capability to record a note at one level it should populate the AllergyIntolerance.note elements with any notes data captured within the system, irrespective of the data level that the system uses to capture that data.
Where a provider system has the capability to record a note at both the AllergyIntolerance and at the AllergyIntolerance.reaction level it should populate both with the relevant notes applicable to each level.
Consumer Systems
Consumer systems MUST be able to handle both multiple AllergyIntolerance.note and multiple AllergyIntolerance.reaction.note elements.
reaction
Details about each adverse reaction event linked to exposure to the identified substance.
The AllergyIntolerance.reaction is optional, but where a severity is available in the provider system it MUST be included to convey severity even if no other reaction details are explicitly available. If this is the case the AllergyIntolerance.reaction.manifestationMUST be coded as the nullFlavor NI.
Element: reaction.substance
An optional element to record the specific substance or pharmaceutical product considered to be responsible for event.
Provider Systems
When recording a reaction to a medication substance, the provider system should use a dm+d concept class.
National Health Service dictionary of medicines and devices combination drug Virtual Therapeutic Moiety (VTM) – just the drugs, no formulation. May be additional concepts to those in the SNOMED-CT hierarchy.
National Health Service dictionary of medicines and devices Virtual Medicinal Product (VMP) - generic drug products and also generic appliance/ device concepts. May be additional concepts to those in the SNOMED-CT hierarchy and will support the recording of allergies to bandages and dressings etc. Device/appliances are concepts that would not be within scope of the SNOMED-CT pharmaceutical/biologic product hierarchy.
National Health Service dictionary of medicines and devices Actual Medicinal Product (AMP) – branded drug products and branded appliance/device concepts that would not be within scope of the SNOMED-CT pharmaceutical/ biologic product hierarchy.
National Health Service dictionary of medicines and devices ingredient – just the drug ingredients, no formulation. May be additional concepts to those in the SNOMED-CT hierarchy. Important to have this in addition to VTM as some things may be more specific at VTM level for example things only available as combinations where VTM would only be the combination also VTM may not identify the salt but this concept class would support that.
Alternatively, the reaction substance can be recorded using a SNOMED CT code from a union of the following.
A mandatory element if a reaction is recorded for the clinical symptoms and/or signs that are observed or associated with the adverse reaction event.
Use nullFlavour NI for the case when a reaction.severity needs to be shared but where a manifestation is not known.
Element: reaction.description
An optional text description about the reaction as a whole, including more verbose details of the manifestation if required.
Element: reaction.onset
An optional date or date/time when the manifestation showed.
This FHIR element may be populated if known.
Element: reaction.severity
An optional value from a required terminology binding containing the values;
mild
moderate
severe
Provider Systems
Where a severity is available in the provider system it MUST be included to convey severity even if no other reaction details are explicitly available.
Where the severity is not known, this element should be omitted.
Consumer Systems
Use of this element when populated as severe may be used to express life threatening allergies, used in conjunction with the AllergyIntolerance.criticality element.
An omitted severity will either mean severity date is not available within the provider system or the severity is not known by the provider system.
Element: reaction.exposureRoute
An optional element to identify the route by which the patient was exposed to the substance.
Consumer systems are recommended not to include this coded information within automated clinical decision support. This is because it could either mean two quite different things;
The reaction only occurs if the substance enters the body via the specified route, implying the use of other routes is safe.
OR
The reaction was identified when the substance entered the body via the specified route, but could also react when using other routes.
Element: reaction.note
An optional element for when the clinical user wishes to provides supporting textual information for the reaction that cannot be conveyed within other elements of the backbone element.
See the related guidance above for AllergyIntolerance.note.
