This page is part of the FHIR Specification (v4.4.0: R5 Preview #2). The current version which supercedes this version is 5.0.0. For a full list of available versions, see the Directory of published versions

11.4 Resource MedicationUsage - Content

Pharmacy

Work Group

Maturity Level: 3

Trial Use

Security Category: Patient

Compartments: Encounter, Patient, Practitioner, RelatedPerson

A record of a medication that is being consumed by a patient. A MedicationUsage may indicate that the patient may be taking the medication now or has taken the medication in the past or will be taking the medication in the future. The source of this information can be the patient, significant other (such as a family member or spouse), or a clinician. A common scenario where this information is captured is during the history taking process during a patient visit or stay. The medication information may come from sources such as the patient's memory, from a prescription bottle, or from a list of medications the patient, clinician or other party maintains.

The primary difference between a medicationusage and a medicationadministration is that the medication administration has complete administration information and is based on actual administration information from the person who administered the medication. A medicationusage is often, if not always, less specific. There is no required date/time when the medication was administered, in fact we only know that a source has reported the patient is taking this medication, where details such as time, quantity, or rate or even medication product may be incomplete or missing or less precise. As stated earlier, the Medication Usage information may come from the patient's memory, from a prescription bottle or from a list of medications the patient, clinician or other party maintains. Medication administration is more formal and is not missing detailed information.

11.4.1 Scope and Usage

Common usage includes:

the recording of non-prescription and/or recreational drugs
the recording of an intake medication list upon admission to hospital
the summarization of a patient's "active medications" in a patient profile

A MedicationUsage may be used to record substance abuse or the use of other agents such as tobacco or alcohol. This would typically be done if these substances are intended to be included in clinical decision support checking (for example, interaction checking) and as part of an active medication list. If the intent is to populate social history and/or to include additional information (for example, desire to quit, amount per day, negative health effects), then it is better to record as an Observation that could then be used to populate Social History.

This resource does not produce a medication list, but it does produce individual medication statements that may be used in the List resource to construct various types of medication lists. Note that other medication lists can also be constructed from the other Pharmacy resources (e.g., MedicationRequest, MedicationAdministration).

A medication statement is not a part of the prescribe -> dispense -> administer sequence, but is a report by a patient, significant other or a clinician that one or more of the prescribe, dispense or administer actions has occurred, resulting is a belief that the patient is, has, or will be using a particular medication.

MedicationUsage is an event resource from a FHIR workflow perspective - see Workflow Event

11.4.2 Boundaries and Relationships

The MedicationUsage resource is used to record a medications or substances that the patient reports as being taken, not taking, have taken in the past or may take in the future. It can also be used to record medication use that is derived from other records such as a MedicationRequest. The statement is not used to request or order a medication, supply or device. When requesting medication, supplies or devices when there is a patient focus or instructions regarding their use, a MedicationRequest, SupplyRequest or DeviceRequest should be used instead

The Medication domain includes a number of related resources

MedicationRequest	An order for both supply of the medication and the instructions for administration of the medicine to a patient.
MedicationDispense	Provision of a supply of a medication with the intention that it is subsequently consumed by a patient (usually in response to a prescription).
MedicationAdministration	When a patient actually consumes a medicine, or it is otherwise administered to them
MedicationUsage	This is a record of a medication being taken by a patient or that a medication has been given to a patient, where the record is the result of a report from the patient or another clinician, or derived from supporting information (for example, Claim, Observation or MedicationRequest). A medication statement is not a part of the prescribe->dispense->administer sequence but is a report that such a sequence (or at least a part of it) did take place, resulting in a belief that the patient has received a particular medication.

This resource is distinct from MedicationRequest, MedicationDispense and MedicationAdministration. Each of those resources refers to specific events - an individual order, an individual provisioning of medication or an individual dosing. MedicationUsage is a broader assertion covering a wider timespan and is independent of specific events. The existence of resource instances of any of the preceding three types may be used to infer a medication statement. However, medication statements can also be captured on the basis of other information, including an assertion by the patient or a care-giver, the results of a lab test, etc.

11.4.3 References

This resource is referenced by AdverseEvent, Goal, itself and Observation.

This resource implements the Event pattern.

Structure

Name	Flags	Card.	Type	Description & Constraints
MedicationUsage	TU		DomainResource	Record of medication being taken by a patient Elements defined in Ancestors: id, meta, implicitRules, language, text, contained, extension, modifierExtension
identifier	Σ	0..*	Identifier	External identifier
basedOn	Σ	0..*	Reference(MedicationRequest \| CarePlan \| ServiceRequest)	Fulfils plan, proposal or order
partOf	Σ	0..*	Reference(MedicationAdministration \| MedicationDispense \| MedicationUsage \| Procedure \| Observation)	Part of referenced event
status	?!Σ	1..1	code	active \| completed \| entered-in-error \| intended \| stopped \| on-hold \| unknown \| not-taken Medication usage status codes (Required)
statusReason		0..*	CodeableConcept	Reason for current status SNOMED CT Drug Therapy Status codes (Example)
category	Σ	0..*	CodeableConcept	Type of medication usage Medication usage administration location codes (Example)
medication	Σ	1..1	CodeableReference(Medication)	What medication was taken SNOMED CT Medication Codes (Example)
subject	Σ	1..1	Reference(Patient \| Group)	Who is/was taking the medication
encounter	Σ	0..1	Reference(Encounter)	Encounter associated with MedicationUsage
effective[x]	Σ	0..1		The date/time or interval when the medication is/was/will be taken
effectiveDateTime			dateTime
effectivePeriod			Period
dateAsserted	Σ	0..1	dateTime	When the usage was asserted?
informationSource		0..1	Reference(Patient \| Practitioner \| PractitionerRole \| RelatedPerson \| Organization)	Person or organization that provided the information about the taking of this medication
derivedFrom		0..*	Reference(Any)	Link to information used to derive the MedicationUsage
reason		0..*	CodeableReference(Condition \| Observation \| DiagnosticReport)	Reason for why the medication is being/was taken Condition/Problem/Diagnosis Codes (Example)
note		0..*	Annotation	Further information about the usage
renderedDosageInstruction		0..1	string	Full representation of the dosage instructions
dosage		0..*	Dosage	Details of how medication is/was taken or should be taken
takenAsOrdered		0..1	boolean	Indicates if the medication is being consumed or administered as prescribed
Documentation for this format

UML Diagram (Legend)

XML Template

<MedicationUsage xmlns="http://hl7.org/fhir"> 
 <!-- from Resource: id, meta, implicitRules, and language -->
 <!-- from DomainResource: text, contained, extension, and modifierExtension -->
 <identifier><!-- 0..* Identifier External identifier --></identifier>
 <basedOn><!-- 0..* Reference(CarePlan|MedicationRequest|ServiceRequest) Fulfils plan, proposal or order --></basedOn>
 <partOf><!-- 0..* Reference(MedicationAdministration|MedicationDispense|
   MedicationUsage|Observation|Procedure) Part of referenced event --></partOf>
 <status value="[code]"/><!-- 1..1 active | completed | entered-in-error | intended | stopped | on-hold | unknown | not-taken -->
 <statusReason><!-- 0..* CodeableConcept Reason for current status --></statusReason>
 <category><!-- 0..* CodeableConcept Type of medication usage --></category>
 <medication><!-- 1..1 CodeableReference(Medication) What medication was taken --></medication>
 <subject><!-- 1..1 Reference(Group|Patient) Who is/was taking  the medication --></subject>
 <encounter><!-- 0..1 Reference(Encounter) Encounter associated with MedicationUsage --></encounter>
 <effective[x]><!-- 0..1 dateTime|Period The date/time or interval when the medication is/was/will be taken --></effective[x]>
 <dateAsserted value="[dateTime]"/><!-- 0..1 When the usage was asserted? -->
 <informationSource><!-- 0..1 Reference(Organization|Patient|Practitioner|
   PractitionerRole|RelatedPerson) Person or organization that provided the information about the taking of this medication --></informationSource>
 <derivedFrom><!-- 0..* Reference(Any) Link to information used to derive the MedicationUsage --></derivedFrom>
 <reason><!-- 0..* CodeableReference(Condition|DiagnosticReport|Observation) Reason for why the medication is being/was taken --></reason>
 <note><!-- 0..* Annotation Further information about the usage --></note>
 <renderedDosageInstruction value="[string]"/><!-- 0..1 Full representation of the dosage instructions -->
 <dosage><!-- 0..* Dosage Details of how medication is/was taken or should be taken --></dosage>
 <takenAsOrdered value="[boolean]"/><!-- 0..1 Indicates if the medication is being consumed or administered as prescribed -->
</MedicationUsage>

JSON Template

{
  "resourceType" : "MedicationUsage",
  // from Resource: id, meta, implicitRules, and language
  // from DomainResource: text, contained, extension, and modifierExtension
  "identifier" : [{ Identifier }], // External identifier
  "basedOn" : [{ Reference(CarePlan|MedicationRequest|ServiceRequest) }], // Fulfils plan, proposal or order
  "partOf" : [{ Reference(MedicationAdministration|MedicationDispense|
   MedicationUsage|Observation|Procedure) }], // Part of referenced event
  "status" : "<code>", // R!  active | completed | entered-in-error | intended | stopped | on-hold | unknown | not-taken
  "statusReason" : [{ CodeableConcept }], // Reason for current status
  "category" : [{ CodeableConcept }], // Type of medication usage
  "medication" : { CodeableReference(Medication) }, // R!  What medication was taken
  "subject" : { Reference(Group|Patient) }, // R!  Who is/was taking  the medication
  "encounter" : { Reference(Encounter) }, // Encounter associated with MedicationUsage
  // effective[x]: The date/time or interval when the medication is/was/will be taken. One of these 2:
  "effectiveDateTime" : "<dateTime>",
  "effectivePeriod" : { Period },
  "dateAsserted" : "<dateTime>", // When the usage was asserted?
  "informationSource" : { Reference(Organization|Patient|Practitioner|
   PractitionerRole|RelatedPerson) }, // Person or organization that provided the information about the taking of this medication
  "derivedFrom" : [{ Reference(Any) }], // Link to information used to derive the MedicationUsage
  "reason" : [{ CodeableReference(Condition|DiagnosticReport|Observation) }], // Reason for why the medication is being/was taken
  "note" : [{ Annotation }], // Further information about the usage
  "renderedDosageInstruction" : "<string>", // Full representation of the dosage instructions
  "dosage" : [{ Dosage }], // Details of how medication is/was taken or should be taken
  "takenAsOrdered" : <boolean> // Indicates if the medication is being consumed or administered as prescribed
}

Turtle Template

@prefix fhir: <http://hl7.org/fhir/> .


[ a fhir:MedicationUsage;
  fhir:nodeRole fhir:treeRoot; # if this is the parser root

  # from Resource: .id, .meta, .implicitRules, and .language
  # from DomainResource: .text, .contained, .extension, and .modifierExtension
  fhir:MedicationUsage.identifier [ Identifier ], ... ; # 0..* External identifier
  fhir:MedicationUsage.basedOn [ Reference(CarePlan|MedicationRequest|ServiceRequest) ], ... ; # 0..* Fulfils plan, proposal or order
  fhir:MedicationUsage.partOf [ Reference(MedicationAdministration|MedicationDispense|MedicationUsage|Observation|
  Procedure) ], ... ; # 0..* Part of referenced event
  fhir:MedicationUsage.status [ code ]; # 1..1 active | completed | entered-in-error | intended | stopped | on-hold | unknown | not-taken
  fhir:MedicationUsage.statusReason [ CodeableConcept ], ... ; # 0..* Reason for current status
  fhir:MedicationUsage.category [ CodeableConcept ], ... ; # 0..* Type of medication usage
  fhir:MedicationUsage.medication [ CodeableReference(Medication) ]; # 1..1 What medication was taken
  fhir:MedicationUsage.subject [ Reference(Group|Patient) ]; # 1..1 Who is/was taking  the medication
  fhir:MedicationUsage.encounter [ Reference(Encounter) ]; # 0..1 Encounter associated with MedicationUsage
  # MedicationUsage.effective[x] : 0..1 The date/time or interval when the medication is/was/will be taken. One of these 2
    fhir:MedicationUsage.effectiveDateTime [ dateTime ]
    fhir:MedicationUsage.effectivePeriod [ Period ]
  fhir:MedicationUsage.dateAsserted [ dateTime ]; # 0..1 When the usage was asserted?
  fhir:MedicationUsage.informationSource [ Reference(Organization|Patient|Practitioner|PractitionerRole|RelatedPerson) ]; # 0..1 Person or organization that provided the information about the taking of this medication
  fhir:MedicationUsage.derivedFrom [ Reference(Any) ], ... ; # 0..* Link to information used to derive the MedicationUsage
  fhir:MedicationUsage.reason [ CodeableReference(Condition|DiagnosticReport|Observation) ], ... ; # 0..* Reason for why the medication is being/was taken
  fhir:MedicationUsage.note [ Annotation ], ... ; # 0..* Further information about the usage
  fhir:MedicationUsage.renderedDosageInstruction [ string ]; # 0..1 Full representation of the dosage instructions
  fhir:MedicationUsage.dosage [ Dosage ], ... ; # 0..* Details of how medication is/was taken or should be taken
  fhir:MedicationUsage.takenAsOrdered [ boolean ]; # 0..1 Indicates if the medication is being consumed or administered as prescribed
]

Changes since R3

This resource did not exist in Release 2

This analysis is available as XML or JSON.

Structure

Name	Flags	Card.	Type	Description & Constraints
MedicationUsage	TU		DomainResource	Record of medication being taken by a patient Elements defined in Ancestors: id, meta, implicitRules, language, text, contained, extension, modifierExtension
identifier	Σ	0..*	Identifier	External identifier
basedOn	Σ	0..*	Reference(MedicationRequest \| CarePlan \| ServiceRequest)	Fulfils plan, proposal or order
partOf	Σ	0..*	Reference(MedicationAdministration \| MedicationDispense \| MedicationUsage \| Procedure \| Observation)	Part of referenced event
status	?!Σ	1..1	code	active \| completed \| entered-in-error \| intended \| stopped \| on-hold \| unknown \| not-taken Medication usage status codes (Required)
statusReason		0..*	CodeableConcept	Reason for current status SNOMED CT Drug Therapy Status codes (Example)
category	Σ	0..*	CodeableConcept	Type of medication usage Medication usage administration location codes (Example)
medication	Σ	1..1	CodeableReference(Medication)	What medication was taken SNOMED CT Medication Codes (Example)
subject	Σ	1..1	Reference(Patient \| Group)	Who is/was taking the medication
encounter	Σ	0..1	Reference(Encounter)	Encounter associated with MedicationUsage
effective[x]	Σ	0..1		The date/time or interval when the medication is/was/will be taken
effectiveDateTime			dateTime
effectivePeriod			Period
dateAsserted	Σ	0..1	dateTime	When the usage was asserted?
informationSource		0..1	Reference(Patient \| Practitioner \| PractitionerRole \| RelatedPerson \| Organization)	Person or organization that provided the information about the taking of this medication
derivedFrom		0..*	Reference(Any)	Link to information used to derive the MedicationUsage
reason		0..*	CodeableReference(Condition \| Observation \| DiagnosticReport)	Reason for why the medication is being/was taken Condition/Problem/Diagnosis Codes (Example)
note		0..*	Annotation	Further information about the usage
renderedDosageInstruction		0..1	string	Full representation of the dosage instructions
dosage		0..*	Dosage	Details of how medication is/was taken or should be taken
takenAsOrdered		0..1	boolean	Indicates if the medication is being consumed or administered as prescribed
Documentation for this format

UML Diagram (Legend)

XML Template

<MedicationUsage xmlns="http://hl7.org/fhir"> 
 <!-- from Resource: id, meta, implicitRules, and language -->
 <!-- from DomainResource: text, contained, extension, and modifierExtension -->
 <identifier><!-- 0..* Identifier External identifier --></identifier>
 <basedOn><!-- 0..* Reference(CarePlan|MedicationRequest|ServiceRequest) Fulfils plan, proposal or order --></basedOn>
 <partOf><!-- 0..* Reference(MedicationAdministration|MedicationDispense|
   MedicationUsage|Observation|Procedure) Part of referenced event --></partOf>
 <status value="[code]"/><!-- 1..1 active | completed | entered-in-error | intended | stopped | on-hold | unknown | not-taken -->
 <statusReason><!-- 0..* CodeableConcept Reason for current status --></statusReason>
 <category><!-- 0..* CodeableConcept Type of medication usage --></category>
 <medication><!-- 1..1 CodeableReference(Medication) What medication was taken --></medication>
 <subject><!-- 1..1 Reference(Group|Patient) Who is/was taking  the medication --></subject>
 <encounter><!-- 0..1 Reference(Encounter) Encounter associated with MedicationUsage --></encounter>
 <effective[x]><!-- 0..1 dateTime|Period The date/time or interval when the medication is/was/will be taken --></effective[x]>
 <dateAsserted value="[dateTime]"/><!-- 0..1 When the usage was asserted? -->
 <informationSource><!-- 0..1 Reference(Organization|Patient|Practitioner|
   PractitionerRole|RelatedPerson) Person or organization that provided the information about the taking of this medication --></informationSource>
 <derivedFrom><!-- 0..* Reference(Any) Link to information used to derive the MedicationUsage --></derivedFrom>
 <reason><!-- 0..* CodeableReference(Condition|DiagnosticReport|Observation) Reason for why the medication is being/was taken --></reason>
 <note><!-- 0..* Annotation Further information about the usage --></note>
 <renderedDosageInstruction value="[string]"/><!-- 0..1 Full representation of the dosage instructions -->
 <dosage><!-- 0..* Dosage Details of how medication is/was taken or should be taken --></dosage>
 <takenAsOrdered value="[boolean]"/><!-- 0..1 Indicates if the medication is being consumed or administered as prescribed -->
</MedicationUsage>

JSON Template

{
  "resourceType" : "MedicationUsage",
  // from Resource: id, meta, implicitRules, and language
  // from DomainResource: text, contained, extension, and modifierExtension
  "identifier" : [{ Identifier }], // External identifier
  "basedOn" : [{ Reference(CarePlan|MedicationRequest|ServiceRequest) }], // Fulfils plan, proposal or order
  "partOf" : [{ Reference(MedicationAdministration|MedicationDispense|
   MedicationUsage|Observation|Procedure) }], // Part of referenced event
  "status" : "<code>", // R!  active | completed | entered-in-error | intended | stopped | on-hold | unknown | not-taken
  "statusReason" : [{ CodeableConcept }], // Reason for current status
  "category" : [{ CodeableConcept }], // Type of medication usage
  "medication" : { CodeableReference(Medication) }, // R!  What medication was taken
  "subject" : { Reference(Group|Patient) }, // R!  Who is/was taking  the medication
  "encounter" : { Reference(Encounter) }, // Encounter associated with MedicationUsage
  // effective[x]: The date/time or interval when the medication is/was/will be taken. One of these 2:
  "effectiveDateTime" : "<dateTime>",
  "effectivePeriod" : { Period },
  "dateAsserted" : "<dateTime>", // When the usage was asserted?
  "informationSource" : { Reference(Organization|Patient|Practitioner|
   PractitionerRole|RelatedPerson) }, // Person or organization that provided the information about the taking of this medication
  "derivedFrom" : [{ Reference(Any) }], // Link to information used to derive the MedicationUsage
  "reason" : [{ CodeableReference(Condition|DiagnosticReport|Observation) }], // Reason for why the medication is being/was taken
  "note" : [{ Annotation }], // Further information about the usage
  "renderedDosageInstruction" : "<string>", // Full representation of the dosage instructions
  "dosage" : [{ Dosage }], // Details of how medication is/was taken or should be taken
  "takenAsOrdered" : <boolean> // Indicates if the medication is being consumed or administered as prescribed
}

Turtle Template

@prefix fhir: <http://hl7.org/fhir/> .


[ a fhir:MedicationUsage;
  fhir:nodeRole fhir:treeRoot; # if this is the parser root

  # from Resource: .id, .meta, .implicitRules, and .language
  # from DomainResource: .text, .contained, .extension, and .modifierExtension
  fhir:MedicationUsage.identifier [ Identifier ], ... ; # 0..* External identifier
  fhir:MedicationUsage.basedOn [ Reference(CarePlan|MedicationRequest|ServiceRequest) ], ... ; # 0..* Fulfils plan, proposal or order
  fhir:MedicationUsage.partOf [ Reference(MedicationAdministration|MedicationDispense|MedicationUsage|Observation|
  Procedure) ], ... ; # 0..* Part of referenced event
  fhir:MedicationUsage.status [ code ]; # 1..1 active | completed | entered-in-error | intended | stopped | on-hold | unknown | not-taken
  fhir:MedicationUsage.statusReason [ CodeableConcept ], ... ; # 0..* Reason for current status
  fhir:MedicationUsage.category [ CodeableConcept ], ... ; # 0..* Type of medication usage
  fhir:MedicationUsage.medication [ CodeableReference(Medication) ]; # 1..1 What medication was taken
  fhir:MedicationUsage.subject [ Reference(Group|Patient) ]; # 1..1 Who is/was taking  the medication
  fhir:MedicationUsage.encounter [ Reference(Encounter) ]; # 0..1 Encounter associated with MedicationUsage
  # MedicationUsage.effective[x] : 0..1 The date/time or interval when the medication is/was/will be taken. One of these 2
    fhir:MedicationUsage.effectiveDateTime [ dateTime ]
    fhir:MedicationUsage.effectivePeriod [ Period ]
  fhir:MedicationUsage.dateAsserted [ dateTime ]; # 0..1 When the usage was asserted?
  fhir:MedicationUsage.informationSource [ Reference(Organization|Patient|Practitioner|PractitionerRole|RelatedPerson) ]; # 0..1 Person or organization that provided the information about the taking of this medication
  fhir:MedicationUsage.derivedFrom [ Reference(Any) ], ... ; # 0..* Link to information used to derive the MedicationUsage
  fhir:MedicationUsage.reason [ CodeableReference(Condition|DiagnosticReport|Observation) ], ... ; # 0..* Reason for why the medication is being/was taken
  fhir:MedicationUsage.note [ Annotation ], ... ; # 0..* Further information about the usage
  fhir:MedicationUsage.renderedDosageInstruction [ string ]; # 0..1 Full representation of the dosage instructions
  fhir:MedicationUsage.dosage [ Dosage ], ... ; # 0..* Details of how medication is/was taken or should be taken
  fhir:MedicationUsage.takenAsOrdered [ boolean ]; # 0..1 Indicates if the medication is being consumed or administered as prescribed
]

Changes since Release 3

This resource did not exist in Release 2

This analysis is available as XML or JSON.

See the Profiles & Extensions and the alternate definitions: Master Definition XML + JSON, XML Schema/Schematron + JSON Schema, ShEx (for Turtle) + see the extensions, the spreadsheet version & the dependency analysis a

11.4.4.1 Terminology Bindings

Path	Definition	Type	Reference
MedicationUsage.status	A coded concept indicating the current status of a MedicationUsage.	Required	MedicationUsage Status Codes
MedicationUsage.statusReason	A coded concept indicating the reason for the status of the statement.	Example	SNOMEDCTDrugTherapyStatusCodes
MedicationUsage.category	A coded concept identifying where the medication included in the MedicationUsage is expected to be consumed or administered.	Example	MedicationUsage Administration Location Codes
MedicationUsage.medication	A coded concept identifying the substance or product being taken.	Example	SNOMEDCTMedicationCodes
MedicationUsage.reason	A coded concept identifying why the medication is being taken.	Example	Condition/Problem/DiagnosisCodes

Path

Definition

Type

Reference

MedicationUsage.status

A coded concept indicating the current status of a MedicationUsage.

Required

MedicationUsage Status Codes

MedicationUsage.statusReason

A coded concept indicating the reason for the status of the statement.

Example

SNOMEDCTDrugTherapyStatusCodes

MedicationUsage.category

A coded concept identifying where the medication included in the MedicationUsage is expected to be consumed or administered.

Example

MedicationUsage Administration Location Codes

MedicationUsage.medication

A coded concept identifying the substance or product being taken.

Example

SNOMEDCTMedicationCodes

MedicationUsage.reason

A coded concept identifying why the medication is being taken.

Example

Condition/Problem/DiagnosisCodes

11.4.5 Search Parameters

Search parameters for this resource. The common parameters also apply. See Searching for more information about searching in REST, messaging, and services.

Name	Type	Description	Expression	In Common
adherence N	token	Returns statements based on adherence or compliance	MedicationUsage.takenAsOrdered
category	token	Returns statements of this category of MedicationUsage	MedicationUsage.category
code D	token	Return statements of this medication code	MedicationUsage.medication.concept	13 Resources
effective	date	Date when patient was taking (or not taking) the medication	MedicationUsage.effective
encounter	reference	Returns statements for a specific encounter	MedicationUsage.encounter (Encounter)
identifier	token	Return statements with this external identifier	MedicationUsage.identifier	30 Resources
medication D	reference	Return statements of this medication reference	MedicationUsage.medication.reference	3 Resources
part-of	reference	Returns statements that are part of another event.	MedicationUsage.partOf (MedicationDispense, Observation, MedicationAdministration, Procedure, MedicationUsage)
patient	reference	Returns statements for a specific patient.	MedicationUsage.subject.where(resolve() is Patient) (Patient)	33 Resources
source	reference	Who or where the information in the statement came from	MedicationUsage.informationSource (Practitioner, Organization, Patient, PractitionerRole, RelatedPerson)
status N	token	Return statements that match the given status	MedicationUsage.status	3 Resources
subject	reference	The identity of a patient, animal or group to list statements for	MedicationUsage.subject (Group, Patient)