Overall quantity of prescribed medication

[rlindstrm]

In eHealth Network guideline, there is an element:

In MyHealth@EU, there is an overall quantity per one package, and a number of packages. In case pack size is not actually defined, number of packages is still mandatory and filled in with "1" (in CDA SubstanceAdministration template supply.quantity) while overall amount is provided in medication object (in CDA ManufacturedMaterial template asContent.quantity).

In FHIR, MedicationRequest.dispenseRequest.quantity is defined as "Amount of medication to supply per dispense", and there is no element for overall prescribed quantity.

Has this been a problem for national services? If so, how has it been solved in national IGs?
Especially interested in cases where multiple dispensations are allowed, but the quantity per one dispensation is not defined.

Issue raised in Xt-EHR Task 6.2 meeting

[rlindstrm]

There's a discussion in Zulip: https://chat.fhir.org/#narrow/stream/179249-Medication/topic/Number.20of.20prescribed.20packages

[rlindstrm]

From Martha:
Regarding the DataSetRevision work in xtEHR 6.2 I have investigated how the different attributes are used in Norway.

Quantity of prescribed product
We have two attributes for describing this in the prescription: Number of packages (0..1 decimal) and Quantity (0..1 PQ). If there is no content in the "number of packages", there shall be content in "quantity". This is typically when the prescriber uses "generic prescription", where neither the actual brand nor package are specified. This is profiled in FHIR as a extention to the MedicationStatement per now: R4 Medication | sfm-reseptamendment - SIMPLIFIER.NET (numberofpackages and amount)

[rlindstrm]

Swedish MedicationList

https://simplifier.net/swedishnationalmedicationlist/nllmedicationrequest
MedicationRequest.dispenseRequest has two extensions:
NumberOfPackagedPrescribed (pos integer)
TotalQuantity (complex extension)

• prescribedQuantity (Quantity)
• remainingQuantity (Quantity)

[rlindstrm]

Samuel Danhardt (Lux)
In Luxembourg you only prescribe a posology, the quantity and the packaging quantity is calculated by the pharmacist according to specific reimbursement rules.

But maybe the problem is the same for the dispense?

[Monstermanu]

In France, as in Luxembourg, you only prescribe a posology. You might translate it into a number of packages if you want but as you prescribe in priority substance or vitual medication, this is rarely done.

[rlindstrm]

Shall I create Jira ticket for this? @costateixeira
Dispense has quantity.
MedicationRequest.dispenseRequest has only quantity per one dispense.

[costateixeira]

I would still like to bring to HL7 the possibility of Dosage being able to nest other Dosages , in which case the parent would contain the overall quantity. We could build a case in a Jira.
This change could also benefit other uses of Dosage, e.g. radiation dosage, etc.