Dosageinstruction-definitions

STU3 Candidate

This page is part of the FHIR Specification (v1.8.0: STU 3 Draft). The current version which supercedes this version is 5.0.0. For a full list of available versions, see the Directory of published versions

?.? DosageInstruction Detailed Descriptions

Clinical Decision Support

Work Group

Maturity Level: N/A

Ballot Status: STU 3

?.?.1 DosageInstruction

DosageInstruction
Definition	Indicates how the medication is to be used by the patient.
Control	1..1
Summary	true
DosageInstruction.sequence
Definition	Indicates the order in which the dosage instructions should be applied or interpreted.
Control	0..1
Type	integer
Requirements	If the sequence number of multiple dosageInstructions is the same, then it is implied that the instructions are to be treated as concurrent. If the sequence number is different, then the dosageInstructions are intended to be sequential.
Summary	true
DosageInstruction.text
Definition	Free text dosage instructions e.g. SIG.
Control	0..1
Type	string
Requirements	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.
Summary	true
DosageInstruction.additionalInstructions
Definition	Supplemental instructions - e.g. "with meals".
Control	0..*
Terminology Binding	SNOMED CT Additional Dosage Instructions (Example)
Type	CodeableConcept
Requirements	Additional instructions such as "Swallow with plenty of water" which may or may not be coded.
Summary	true
DosageInstruction.timing
Definition	When medication should be administered.
Control	0..1
Type	Timing
Requirements	The timing schedule for giving the medication to the patient. The Schedule 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.
Summary	true
To Do	This attribute may not always be populated while the DosageInstruction.text is expected to be populated. If both are populated, then the DosageInstruction.text should reflect the content of the Dosage.timing.
DosageInstruction.asNeeded[x]
Definition	Take "as needed" (for x).
Control	0..1
Terminology Binding	SNOMED CT Medication As Needed Reason Codes (Example)
Type	boolean\|CodeableConcept
[x] Note	See Choice of Data Types for further information about how to use [x]
Requirements	Indicates whether the Medication is only taken when needed within a specific dosing schedule (Boolean option), or it indicates the precondition for taking the Medication (CodeableConcept).
Summary	true
To Do	Specifically if 'boolean' datatype is selected, then the following logic applies: If set to True, this indicates that the medication is only taken when needed, within the specified schedule.
DosageInstruction.site
Definition	Body site to administer to.
Control	0..1
Terminology Binding	SNOMED CT Anatomical Structure for Administration Site Codes (Example)
Type	CodeableConcept
Requirements	A coded specification of the anatomic site where the medication first enters the body.
Summary	true
Comments	If the use case requires attributes from the BodySite resource (e.g. to identify and track separately) then use the standard extension body-site-instance. May be a summary code, or a reference to a very precise definition of the location, or both.
DosageInstruction.route
Definition	How drug should enter body.
Control	0..1
Terminology Binding	SNOMED CT Route Codes (Example)
Type	CodeableConcept
Requirements	A code specifying the route or physiological path of administration of a therapeutic agent into or onto a patient's body.
Summary	true
DosageInstruction.method
Definition	Technique for administering medication.
Control	0..1
Terminology Binding	SNOMED CT Administration Method Codes (Example)
Type	CodeableConcept
Requirements	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.
Summary	true
To Do	Terminologies used often pre-coordinate this term with the route and or form of administration.
DosageInstruction.dose[x]
Definition	Amount of medication per dose.
Control	0..1
Type	Range\|SimpleQuantity
[x] Note	See Choice of Data Types for further information about how to use [x]
Requirements	The amount of therapeutic or other substance given at one administration event.
Summary	true
To Do	Note that this specifies the quantity of the specified medication, not the quantity for each active ingredient(s). Each ingredient amount can be communicated in the Medication resource. For example, if one wants to communicate that a tablet was 375 mg, where the dose was one tablet, you can use the Medication resource to document that the tablet was comprised of 375 mg of drug XYZ. Alternatively if the dose was 375 mg, then you may only need to use the Medication resource to indicate this was a tablet. If the example were an IV such as dopamine and you wanted to communicate that 400mg of dopamine was mixed in 500 ml of some IV solution, then this would all be communicated in the Medication resource. If the administration is not intended to be instantaneous (rate is present or timing has a duration), this can be specified to convey the total amount to be administered over the period of time as indicated by the schedule e.g. 500 ml in dose, with timing used to convey that this should be done over 4 hours.
DosageInstruction.maxDosePerPeriod
Definition	Upper limit on medication per unit of time.
Control	0..1
Type	Ratio
Requirements	The maximum total quantity of a therapeutic substance that may be administered to a subject over the period of time. For example, 1000mg in 24 hours.
Summary	true
To Do	This is intended for use as an adjunct to the dosage when there is an upper cap. For example "2 tablets every 4 hours to a maximum of 8/day".
DosageInstruction.maxDosePerAdministration
Definition	Upper limit on medication per administration.
Control	0..1
Type	SimpleQuantity
Requirements	The maximum total quantity of a therapeutic substance that may be administered to a subject per administration.
Summary	true
To Do	This is intended for use as an adjunct to the dosage when there is an upper cap. For example, a body surface area related dose with a maximum amount, such as 1.5 mg/m2 (maximum 2 mg) IV over 5 – 10 minutes would have doseQuantity of 1.5 mg/m2 and maxDosePerAdministration of 2 mg.
DosageInstruction.maxDosePerLifetime
Definition	Upper limit on medication per lifetime of the patient.
Control	0..1
Type	SimpleQuantity
Requirements	The maximum total quantity of a therapeutic substance that may be administered per lifetime of the subject.
Summary	true
DosageInstruction.rate[x]
Definition	Amount of medication per unit of time.
Control	0..1
Type	Ratio\|Range\|SimpleQuantity
[x] Note	See Choice of Data Types for further information about how to use [x]
Requirements	Identifies the speed with which the medication was or will be introduced into the patient. Typically the rate for an infusion e.g. 100 ml per 1 hour or 100 ml/hr. May also be expressed as a rate per unit of time e.g. 500 ml per 2 hours. Other examples: 200 mcg/min or 200 mcg/1 minute; 1 liter/8 hours. 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.
Summary	true
To Do	It is possible to supply both a rate and a doseQuantity to provide full details about how the medication is to be administered and supplied. If the rate is intended to change over time, depending on local rules/regulations, each change should be captured as a new version of the MedicationRequest with an updated rate, or captured with a new MedicationRequest with the new rate.