*This Profile can represent a medication using a code or reference a Medication resource.

When using a code, RXNorm concepts are used. They are defined as an extensible binding to .medicationCodeableConcept. USCDI V3+ recommends the National Drug Codes (NDC) as an optional terminology. They can be supplied as an additional coding element.

A clarification is needed.  The excerpt above requires the use of RXNorm concepts and permits a second coding element to contain an NDC.  There are real-life use cases where NDC is the expected medication code and RXNorm is not used (not relevant to the interaction).  In particular, Prescription Drug Monitoring Programs (PDMPs) use NDC when exchanging dispense records and do not support (does not have access to) RXNorm concepts.  In such cases, would it be appropriate to only send NDC?  If not, how can such systems conform to the US Core MedicationDispense profile?