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

A reference to a set of rules that were followed when the resource was constructed, and which must be understood when processing the content.

Asserting this rule set restricts the content to be only understood by a limited set of trading partners. This inherently limits the usefulness of the data in the long term. However, the existing health eco-system is highly fractured, and not yet ready to define, collect, and exchange data in a generally computable sense. Wherever possible, implementers and/or specification writers should avoid using this element.

This element is labelled as a modifier because the implicit rules may provide additional knowledge about the resource that modifies it's meaning or interpretation.

An Extension

R5: AllergyIntolerance.encounter (new:Reference(Encounter))

Element AllergyIntolerance.encounter has a context of AllergyIntolerance based on following the parent source element upwards and mapping to AllergyIntolerance. Element AllergyIntolerance.encounter has no mapping targets in FHIR STU3. Typically, this is because the element has been added (is a new element).

R5: AllergyIntolerance.participant (new:BackboneElement)

Element AllergyIntolerance.participant has a context of AllergyIntolerance based on following the parent source element upwards and mapping to AllergyIntolerance. Element AllergyIntolerance.participant has no mapping targets in FHIR STU3. Typically, this is because the element has been added (is a new element).

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

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.

The clinical status of the allergy or intolerance.

This element is labeled as a modifier because the status contains the codes inactive and resolved that mark the AllergyIntolerance as not currently valid.

The clinical status of the allergy or intolerance.

An Extension

R5: AllergyIntolerance.clinicalStatus additional types (CodeableConcept) additional types from child elements (coding)

Element AllergyIntolerance.clinicalStatus is mapped to FHIR STU3 element AllergyIntolerance.clinicalStatus as SourceIsBroaderThanTarget. The mappings for AllergyIntolerance.clinicalStatus do not cover the following types: CodeableConcept. The mappings for AllergyIntolerance.clinicalStatus do not cover the following types based on type expansion: coding. The target context AllergyIntolerance.clinicalStatus is a modifier element, so this extension does not need to be defined as a modifier. AllergyIntolerance.clinicalStatus should be present if verificationStatus is not entered-in-error and the AllergyIntolerance.code isn't negated (No Known Allergy, No Drug Allergy, No Food Allergy, No Latex Allergy). Refer to discussion if clinicalStatus 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).

This element is labeled as a modifier because the status contains the codes refuted and entered-in-error that mark the AllergyIntolerance as not currently valid.

Assertion about certainty associated with a propensity, or potential risk, of a reaction to the identified substance.

An Extension

R5: AllergyIntolerance.verificationStatus additional types (CodeableConcept) additional types from child elements (coding)

Element AllergyIntolerance.verificationStatus is mapped to FHIR STU3 element AllergyIntolerance.verificationStatus as SourceIsBroaderThanTarget. The mappings for AllergyIntolerance.verificationStatus do not cover the following types: CodeableConcept. The mappings for AllergyIntolerance.verificationStatus do not cover the following types based on type expansion: coding. The target context AllergyIntolerance.verificationStatus is a modifier element, so this extension does not need to be defined as a modifier. 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.

The patient who has the allergy or intolerance.

An Extension

R5: AllergyIntolerance.patient additional types from child elements (display, identifier, reference, type)

Element AllergyIntolerance.patient is mapped to FHIR STU3 element AllergyIntolerance.patient as SourceIsBroaderThanTarget. The mappings for AllergyIntolerance.patient do not cover the following types based on type expansion: display, identifier, reference, type. The standard extension alternate-reference has been mapped as the representation of FHIR R5 element AllergyIntolerance.patient with unmapped reference targets: Patient.

R5: AllergyIntolerance.encounter (new:Reference(Encounter))

Element AllergyIntolerance.encounter has a context of AllergyIntolerance based on following the parent source element upwards and mapping to AllergyIntolerance. Element AllergyIntolerance.encounter has no mapping targets in FHIR STU3. Typically, this is because the element has been added (is a new element).

R5: AllergyIntolerance.participant (new:BackboneElement)

Element AllergyIntolerance.participant has a context of AllergyIntolerance based on following the parent source element upwards and mapping to AllergyIntolerance. Element AllergyIntolerance.participant has no mapping targets in FHIR STU3. Typically, this is because the element has been added (is a new element).

R5: AllergyIntolerance.clinicalStatus additional types (CodeableConcept) additional types from child elements (coding)

Element AllergyIntolerance.clinicalStatus is mapped to FHIR STU3 element AllergyIntolerance.clinicalStatus as SourceIsBroaderThanTarget. The mappings for AllergyIntolerance.clinicalStatus do not cover the following types: CodeableConcept. The mappings for AllergyIntolerance.clinicalStatus do not cover the following types based on type expansion: coding. The target context AllergyIntolerance.clinicalStatus is a modifier element, so this extension does not need to be defined as a modifier. AllergyIntolerance.clinicalStatus should be present if verificationStatus is not entered-in-error and the AllergyIntolerance.code isn't negated (No Known Allergy, No Drug Allergy, No Food Allergy, No Latex Allergy). Refer to discussion if clinicalStatus 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.

R5: AllergyIntolerance.verificationStatus additional types (CodeableConcept) additional types from child elements (coding)

Element AllergyIntolerance.verificationStatus is mapped to FHIR STU3 element AllergyIntolerance.verificationStatus as SourceIsBroaderThanTarget. The mappings for AllergyIntolerance.verificationStatus do not cover the following types: CodeableConcept. The mappings for AllergyIntolerance.verificationStatus do not cover the following types based on type expansion: coding. The target context AllergyIntolerance.verificationStatus is a modifier element, so this extension does not need to be defined as a modifier. 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.

R5: AllergyIntolerance.type additional types (CodeableConcept) additional types from child elements (coding)

Element AllergyIntolerance.type is mapped to FHIR STU3 element AllergyIntolerance.type as SourceIsBroaderThanTarget. The mappings for AllergyIntolerance.type do not cover the following types: CodeableConcept. The mappings for AllergyIntolerance.type do not cover the following types based on type expansion: coding. 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.

R5: AllergyIntolerance.patient additional types from child elements (display, identifier, reference, type)

Element AllergyIntolerance.patient is mapped to FHIR STU3 element AllergyIntolerance.patient as SourceIsBroaderThanTarget. The mappings for AllergyIntolerance.patient do not cover the following types based on type expansion: display, identifier, reference, type. The standard extension alternate-reference has been mapped as the representation of FHIR R5 element AllergyIntolerance.patient with unmapped reference targets: Patient.

R5: AllergyIntolerance.reaction.manifestation additional types (CodeableReference(http://hl7.org/fhir/StructureDefinition/Observation)) additional types from child elements (reference)

Element AllergyIntolerance.reaction.manifestation is mapped to FHIR STU3 element AllergyIntolerance.reaction.manifestation as SourceIsBroaderThanTarget. The mappings for AllergyIntolerance.reaction.manifestation do not cover the following types: CodeableReference. The mappings for AllergyIntolerance.reaction.manifestation do not cover the following types based on type expansion: reference. 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.

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

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

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

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

A reference to a set of rules that were followed when the resource was constructed, and which must be understood when processing the content.

Asserting this rule set restricts the content to be only understood by a limited set of trading partners. This inherently limits the usefulness of the data in the long term. However, the existing health eco-system is highly fractured, and not yet ready to define, collect, and exchange data in a generally computable sense. Wherever possible, implementers and/or specification writers should avoid using this element.

This element is labelled as a modifier because the implicit rules may provide additional knowledge about the resource that modifies it's meaning or interpretation.

The base language in which the resource is written.

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

Unless not suitable, these codes SHALL be taken from Common Languages
(extensible to http://hl7.org/fhir/ValueSet/languages|3.0.2)

A human language.

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

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

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

This should never be done when the content can be identified properly, as once identification is lost, it is extremely difficult (and context dependent) to restore it again.

An Extension

R5: AllergyIntolerance.encounter (new:Reference(Encounter))

Element AllergyIntolerance.encounter has a context of AllergyIntolerance based on following the parent source element upwards and mapping to AllergyIntolerance. Element AllergyIntolerance.encounter has no mapping targets in FHIR STU3. Typically, this is because the element has been added (is a new element).

R5: AllergyIntolerance.participant (new:BackboneElement)

Element AllergyIntolerance.participant has a context of AllergyIntolerance based on following the parent source element upwards and mapping to AllergyIntolerance. Element AllergyIntolerance.participant has no mapping targets in FHIR STU3. Typically, this is because the element has been added (is a new element).

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

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.

This records identifiers associated with this allergy/intolerance concern that are defined by business processes and/or used to refer to it when a direct URL reference to the resource itself is not appropriate (e.g. in CDA documents, or in written / printed documentation).

The clinical status of the allergy or intolerance.

This element is labeled as a modifier because the status contains the codes inactive and resolved that mark the AllergyIntolerance as not currently valid.

The clinical status of the allergy or intolerance.

unique id for the element within a resource (for internal references)

An Extension

R5: AllergyIntolerance.clinicalStatus additional types (CodeableConcept) additional types from child elements (coding)

Element AllergyIntolerance.clinicalStatus is mapped to FHIR STU3 element AllergyIntolerance.clinicalStatus as SourceIsBroaderThanTarget. The mappings for AllergyIntolerance.clinicalStatus do not cover the following types: CodeableConcept. The mappings for AllergyIntolerance.clinicalStatus do not cover the following types based on type expansion: coding. The target context AllergyIntolerance.clinicalStatus is a modifier element, so this extension does not need to be defined as a modifier. AllergyIntolerance.clinicalStatus should be present if verificationStatus is not entered-in-error and the AllergyIntolerance.code isn't negated (No Known Allergy, No Drug Allergy, No Food Allergy, No Latex Allergy). Refer to discussion if clinicalStatus 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.

Primitive value for code

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

This element is labeled as a modifier because the status contains the codes refuted and entered-in-error that mark the AllergyIntolerance as not currently valid.

Assertion about certainty associated with a propensity, or potential risk, of a reaction to the identified substance.

unique id for the element within a resource (for internal references)

An Extension

R5: AllergyIntolerance.verificationStatus additional types (CodeableConcept) additional types from child elements (coding)

Element AllergyIntolerance.verificationStatus is mapped to FHIR STU3 element AllergyIntolerance.verificationStatus as SourceIsBroaderThanTarget. The mappings for AllergyIntolerance.verificationStatus do not cover the following types: CodeableConcept. The mappings for AllergyIntolerance.verificationStatus do not cover the following types based on type expansion: coding. The target context AllergyIntolerance.verificationStatus is a modifier element, so this extension does not need to be defined as a modifier. 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.

Primitive value for code

Identification of the underlying physiological mechanism for the reaction risk.

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 may 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 may 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.

Identification of the underlying physiological mechanism for a Reaction Risk.

unique id for the element within a resource (for internal references)

An Extension

R5: AllergyIntolerance.type additional types (CodeableConcept) additional types from child elements (coding)

Element AllergyIntolerance.type is mapped to FHIR STU3 element AllergyIntolerance.type as SourceIsBroaderThanTarget. The mappings for AllergyIntolerance.type do not cover the following types: CodeableConcept. The mappings for AllergyIntolerance.type do not cover the following types based on type expansion: coding. 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.

Primitive value for code

Category of the identified substance.

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.

Category of an identified substance.

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

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.

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

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").

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, UNI, ATC and CPT. 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.

Type of the substance/product, allergy or intolerance condition, or negation/exclusion codes for reporting no known allergies.

The patient who has the allergy or intolerance.

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

An Extension

R5: AllergyIntolerance.patient additional types from child elements (display, identifier, reference, type)

Element AllergyIntolerance.patient is mapped to FHIR STU3 element AllergyIntolerance.patient as SourceIsBroaderThanTarget. The mappings for AllergyIntolerance.patient do not cover the following types based on type expansion: display, identifier, reference, type. The standard extension alternate-reference has been mapped as the representation of FHIR R5 element AllergyIntolerance.patient with unmapped reference targets: Patient.

A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources.

Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server.

An identifier for the other resource. This is used when there is no way to reference the other resource directly, either because the entity is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference.

When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy.

When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference

Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it.

Plain text narrative that identifies the resource in addition to the resource reference.

This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it.

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

The date on which the existance of the AllergyIntolerance was first asserted or acknowledged.

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

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

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

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

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.

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

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.

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

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

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

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.

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

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.

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'.

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 identifed 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'.

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

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

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.

Clinical symptoms and/or signs that are observed or associated with an Adverse Reaction Event.

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

An Extension

R5: AllergyIntolerance.reaction.manifestation additional types (CodeableReference(http://hl7.org/fhir/StructureDefinition/Observation)) additional types from child elements (reference)

Element AllergyIntolerance.reaction.manifestation is mapped to FHIR STU3 element AllergyIntolerance.reaction.manifestation as SourceIsBroaderThanTarget. The mappings for AllergyIntolerance.reaction.manifestation do not cover the following types: CodeableReference. The mappings for AllergyIntolerance.reaction.manifestation do not cover the following types based on type expansion: reference. 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.

A reference to a code defined by a terminology system.

Codes may be defined very casually in enumerations, or code lists, up to very formal definitions such as SNOMED CT - see the HL7 v3 Core Principles for more information. Ordering of codings is undefined and SHALL NOT be used to infer meaning. Generally, at most only one of the coding values will be labeled as UserSelected = true.

Allows for translations and alternate encodings within a code system. Also supports communication of the same instance to systems requiring different encodings.

A human language representation of the concept as seen/selected/uttered by the user who entered the data and/or which represents the intended meaning of the user.

Very often the text is the same as a displayName of one of the codings.

The codes from the terminologies do not always capture the correct meaning with all the nuances of the human using them, or sometimes there is no appropriate code at all. In these cases, the text is used to capture the full meaning of the source.

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

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.

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

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

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

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

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

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

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

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

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.