---
type: "datatype"
title: "Dosage"
datatype: "Dosage"
---
# Dosage

- [Datatypes](/datatypes)
- [Definitions](/datatypes-definitions#Dosage)
- [Examples](/datatypes-examples#Dosage)
- [Mappings](/datatypes-mappings#Dosage)
- [Profiles](/datatypes-profiles#Dosage)

## Elements

- **[Dosage.condition](/datatypes-definitions#Dosage.condition)** [0..*]: [DosageCondition](/DosageCondition) Whether the dosage applies (e.g. as a whole). The Disage applies if any of the conditions are true
- **[Dosage.text](/datatypes-definitions#Dosage.text)** [0..1]: [string](/string) Free text dosage instructions e.g. SIG
- **[Dosage.additionalInstruction](/datatypes-definitions#Dosage.additionalInstruction)** [0..*]: [CodeableConcept](/CodeableConcept) Supplemental instructions to the patient on how to take the medication (e.g. "with meals" or"take half to one hour before food") or warnings for the patient about the medication (e.g. "may cause drowsiness" or "avoid exposure of skin to direct sunlight or sunlamps")
- **[Dosage.patientInstruction](/datatypes-definitions#Dosage.patientInstruction)** [0..1]: [string](/string) Instructions in terms that are understood by the patient or consumer
- **[Dosage.timing](/datatypes-definitions#Dosage.timing)** [0..1]: [Timing](/Timing) When medication should be administered
- **[Dosage.asNeeded](/datatypes-definitions#Dosage.asNeeded)** [0..1]: [boolean](/boolean) Indicates whether the Medication is only taken when needed within a specific dosing schedule (Boolean option)
- **[Dosage.asNeededFor](/datatypes-definitions#Dosage.asNeededFor)** [0..*]: [CodeableConcept](/CodeableConcept) Indicates whether the Medication is only taken based on a precondition for taking the Medication (CodeableConcept).
- **[Dosage.site](/datatypes-definitions#Dosage.site)** [0..1]: [CodeableConcept](/CodeableConcept) Body site to administer to
- **[Dosage.route](/datatypes-definitions#Dosage.route)** [0..1]: [CodeableConcept](/CodeableConcept) How drug should enter body
- **[Dosage.method](/datatypes-definitions#Dosage.method)** [0..1]: [CodeableConcept](/CodeableConcept) Technique for administering medication
- **[Dosage.doseAndRate](/datatypes-definitions#Dosage.doseAndRate)** [0..*]: - Depending on the resource,this is the amount of medication administered, to be administered or typical amount to be administered.
- **[Dosage.safety](/datatypes-definitions#Dosage.safety)** [0..1]: [DosageSafety](/DosageSafety) Safety Information about the this dosage instructions

## Bindings

- **Dosage.additionalInstruction**: `AdditionalInstruction` | strength: value set | reference: valueset-additional-instruction-codes
- **Dosage.asNeededFor**: `MedicationAsNeededReason` | strength: value set | reference: valueset-medication-as-needed-reason
- **Dosage.site**: `MedicationAdministrationSite` | strength: value set | reference: valueset-approach-site-codes
- **Dosage.route**: `RouteOfAdministration` | strength: value set | reference: valueset-route-codes
- **Dosage.method**: `MedicationAdministrationMethod` | strength: value set | reference: valueset-administration-method-codes

## Requirements

- **Dosage.text**: Free text dosage instructions can be used for cases where the instructions are too complex to code. The content of this attribute does not include the name or description of the medication. When coded instructions are present, the free text instructions may still be present for display to humans taking or administering the medication. It is expected that the text instructions will always be populated. If the dosage.timing attribute is also populated, then the dosage.text should reflect the same information as the timing. Additional information about administration or preparation of the medication should be included as text.
- **Dosage.additionalInstruction**: Additional instruction is intended to be coded, but where no code exists, the element could include text. For example, "Swallow with plenty of water" which might or might not be coded.
- **Dosage.timing**: The timing schedule for giving the medication to the patient. This data type allows many different expressions. For example: "Every 8 hours"; "Three times a day"; "1/2 an hour before breakfast for 10 days from 23-Dec 2011:"; "15 Oct 2013, 17 Oct 2013 and 1 Nov 2013". Sometimes, a rate can imply duration when expressed as total volume / duration (e.g. 500mL/2 hours implies a duration of 2 hours). However, when rate doesn't imply duration (e.g. 250mL/hour), then the timing.repeat.duration is needed to convey the infuse over time period.
- **Dosage.site**: A coded specification of the anatomic site where the medication first enters the body
- **Dosage.route**: A code specifying the route or physiological path of administration of a therapeutic agent into or onto a patient's body.
- **Dosage.method**: A coded value indicating the method by which the medication is introduced into or onto the body. Most commonly used for injections. For examples, Slow Push; Deep IV.

## Comments

- **Dosage.additionalInstruction**: Information about administration or preparation of the medication (e.g. "infuse as rapidly as possibly via intraperitoneal port" or take "immediately following drug x") should be populated in dosage.text
- **Dosage.timing**: This attribute might not always be populated while the Dosage.text is expected to be populated. If both are populated, then the Dosage.text should reflect the content of the Dosage.timing.
- **Dosage.asNeeded**: Can express "as needed" without a reason by setting the Boolean = True. In this case the CodeableConcept is not populated.
- **Dosage.asNeededFor**: Can express "as needed" with a reason by including the CodeableConcept. Based on the invariant, the Dosage.asNeededFor is not populated when Dosage.asNeeded is false. If the Dosage.asNeeded is "false", then the dose is given according to the schedule and is not "prn" or "as needed"
- **Dosage.site**: If the use case requires attributes from the BodySite resource (e.g. to identify and track separately) then use the standard extension [[[http://hl7.org/fhir/StructureDefinition/bodySite]]]. May be a summary code, or a reference to a very precise definition of the location, or both
- **Dosage.method**: Terminologies used often pre-coordinate this term with the route and or form of administration.

## Mappings

- **Dosage.text**: RIM Mapping: .text
- **Dosage.text**: v2 Mapping: RXO-6; RXE-21
- **Dosage.text**: ??? Mapping: RXE-7.2-Provider's Administration Instructions.text / RXO-7.2-Provider's Administration Instructions.text / TQ1-10-Condition Text / TQ1-11-Text Instruction
- **Dosage.additionalInstruction**: RIM Mapping: .text
- **Dosage.additionalInstruction**: v2 Mapping: RXO-7
- **Dosage.additionalInstruction**: ??? Mapping: RXE-7.2-Provider's Administration Instructions.text / RXO-7.2-Provider's Administration Instructions.text / TQ1-10-Condition Text / TQ1-11-Text Instruction
- **Dosage.additionalInstruction**: ??? Mapping: //element(*,SIGType)/Timing
- **Dosage.patientInstruction**: RIM Mapping: .text
- **Dosage.patientInstruction**: v2 Mapping: RXO-7
- **Dosage.timing**: RIM Mapping: .effectiveTime
- **Dosage.timing**: ??? Mapping: TQ1-X / ORC Quantity/timing
- **Dosage.timing**: ??? Mapping: //element(*,SIGType)/SiteofAdministration
- **Dosage.asNeeded**: RIM Mapping: .outboundRelationship[typeCode=PRCN].target[classCode=OBS, moodCode=EVN, code="as needed"].value=boolean or codable concept
- **Dosage.asNeeded**: v2 Mapping: TQ1-9
- **Dosage.asNeeded**: ??? Mapping: Message/Body/NewRx/MedicationPrescribed/StructuredSIG/SiteofAdministration
- **Dosage.asNeededFor**: RIM Mapping: .outboundRelationship[typeCode=PRCN].target[classCode=OBS, moodCode=EVN, code="as needed"].value=boolean or codable concept
- **Dosage.asNeededFor**: v2 Mapping: TQ1-9
- **Dosage.asNeededFor**: ??? Mapping: Message/Body/NewRx/MedicationPrescribed/StructuredSIG/SiteofAdministration
- **Dosage.site**: RIM Mapping: .approachSiteCode
- **Dosage.site**: v2 Mapping: RXR-2
- **Dosage.site**: ??? Mapping: RXR-2-Administration Site
- **Dosage.site**: ??? Mapping: //element(*,SIGType)/RouteofAdministration
- **Dosage.route**: RIM Mapping: .routeCode
- **Dosage.route**: v2 Mapping: RXR-1
- **Dosage.route**: ??? Mapping: RXR-1-Route
- **Dosage.route**: ??? Mapping: //element(*,SIGType)/Dose/DoseDeliveryMethodCode
- **Dosage.method**: RIM Mapping: SubstanceAdministration.methodCode
- **Dosage.method**: v2 Mapping: RXR-4
- **Dosage.method**: ??? Mapping: RXR-4-Administration Method
- **Dosage.method**: ??? Mapping: //element(*,SIGType)/Dose
- **Dosage.doseAndRate**: RIM Mapping: SubstanceAdministration.doseQuantity; SubstanceAdministration.RateQuantity
- **Dosage.doseAndRate**: v2 Mapping: TQ1-2