RxChange Message

Overview

RxChange is a type of message sent by pharmacy to subscriber when the medication should be changed to a different one. It is required that RxChange is preceded by NewRx.

Note: The pharmacy may include a ChangeReasonText field containing the reason for requesting a medication change. This information is stored in the MedicationRequest resource as an extension MedicationRequest.extension.where(url = "http://aidbox.app/ePrescription/FHIRSchema/medication-request-rx-change-change-reason-text ")

Decisions use cases

Example 1: The pharmacy sent an RxChange request to the prescriber proposing to substitute the unavailable Lipitor 20 mg with Atorvastatin 20 mg under the same parameters. The prescriber agreed to the substitution without any changes and sent an RxChangeResponse with the Approved type, allowing the pharmacy to dispense the generic instead of the brand product. So approved response should be used.

Example 2: The pharmacy sent an RxChange request proposing to substitute the unavailable Lipitor 20 mg with Atorvastatin 20 mg as one of the MedicationRequested options. The prescriber responded with an RxChangeResponse of type approved-with-changes for the same patient, selecting the requested Atorvastatin but changing the directions from "take one tablet daily" to "take two tablets daily" and instructing the pharmacy to cancel the original prescription and dispense the updated one.

Example 3: The pharmacy sent an RxChange request proposing to substitute the unavailable Lipitor 20 mg with Atorvastatin 20 mg. The prescriber responded with an RxChangeResponse of type denied for the same patient, providing ReasonCode: "Patient allergy to the proposed product".

Example 4: The pharmacy sent an RxChange request proposing to substitute Lipitor 20 mg with Atorvastatin 20 mg. The prescriber responded with an RxChangeResponse of type pending, indicating that a decision could not yet be made and that further review was required. The prescriber must wait for subsequent RxChangeRequest messages from the pharmacy, as once a request has been answered with pending, it cannot later be responded to again with approved or denied for the same transaction.

Example 5: The pharmacy sent an RxChange request for Prescriber Authorization with MessageRequestCode = U and MessageRequestSubCodes = [G, B] requesting the prescriber's NPI and DEA number. The prescriber replied with an RxChangeResponse of type Validated, echoing MessageRequestCode = U and SubCodes G and B, providing ResponseReasonCode = GM for each and populating NPI with "1234567890" and DEANumber with "AB1234567" to confirm active registration.

Supported Request Types

• D: Drug Use Evaluation
• G: Generic Substitution - A modification of the product prescribed to a generic equivalent.
• OS: Pharmacy is out of stock of the medication prescribed and it cannot be obtained in a clinically appropriate timeframe.
• S: Script Clarification
• T: Therapeutic Interchange/Substitution - A modification of the product prescribed to a preferred product choice
• RM: REMS dispensing authorization requirements not met
• U: Prescriber Authorization – Resolution of the prescriber authorization conflict related to state/federal regulatory requirements is required before dispensing.
  • This is the only message type Validated response type can be used for.

Responding to RxChangeRequest

Setting a decision

Available decisions are approved, approved-with-changes, denied, pending or validated. It is represented as an extension:

extension:
  - url: >-
      http://aidbox.app/ePrescription/FHIRSchema/medication-request-rx-change-decision
    valueCode: denied

Table of compatibility between decisions and request types:

Denied

_{Same as for RxRenewal.}

denied is the decision that requires the least amount of steps. Setting it in the extension is the only requirement. You can set the denial reason (free text) in decision note extension ( http://aidbox.app/ePrescription/FHIRSchema/medication-request-rx-change-decision-note), but this is optional. Call the /eprescription/rx/respond-to-change endpoint to commit your decision:

POST /eprescription/rx/respond-to-change

{
  "medicationRequestId": "your-medication-request-id"
}

Pending

_{Same as for RxRenewal.}

Before committing the pending decision you need to

Set the decision itself:

extension:
  - url: >-
      http://aidbox.app/ePrescription/FHIRSchema/medication-request-rx-change-decision
    valueCode: pending

Set the expected pended response date:

extension:
  - url: >-
      http://aidbox.app/ePrescription/FHIRSchema/medication-request-rx-change-expected-pended-response-date
    valueDate: '2025-12-12'

Set the decision note (contrarily to denied decision, it's required for pending):

extension:
  - url: >-
      http://aidbox.app/ePrescription/FHIRSchema/medication-request-rx-change-decision-note
    valueString: Provider is on vacation

Set the reason code:

extension:
  - url: >-
      http://aidbox.app/ePrescription/FHIRSchema/medication-request-rx-change-decision-reason-code
    valueCodeableConcept:
      coding:
        - code: HR
          system: urn:app:aidbox:e-prescriptions:surescripts:decision-reason-code
          display: Provider is unavailable and no one is available to make a decision

Available reason codes are listed in the table below (same for RxChange case):

Approved

Use this decision when medication change was allowed unaltered. No changes allowed to the stored MedicationRequest and the resources it references.

Set the decision:

extension:
  - url: >-
      http://aidbox.app/ePrescription/FHIRSchema/medication-request-rx-change-decision
    valueCode: approved

Set MedicationRequest.dispenseRequest, MedicationRequest.dosageInstruction and MedicationRequest.medication the way it reflects the data from one of the suggested changes.

...
contained:
- substitution: {allowedBoolean: true}
  dispenseRequest:
    quantity: {code: C48480, value: 20.0, system: 'urn:app:aidbox:e-prescriptions:ncpdp:QuantityUnitOfMeasure'}
    expectedSupplyDuration: {code: d, unit: days, value: 10, system: 'http://unitsofmeasure.org'}
    numberOfRepeatsAllowed: 1
  medicationCodeableConcept:
    text: doxycycline hyclate 100 mg capsule
    coding:
    - {code: '00143314250', system: 'http://hl7.org/fhir/sid/ndc'}
  resourceType: MedicationRequest
  dosageInstruction:
  - {text: Take 1 capsule orally every 12 hours for 10 days}
  ...
- substitution: {allowedBoolean: false}
  dispenseRequest:
    quantity: {code: C48542, value: 150.0, system: 'urn:app:aidbox:e-prescriptions:ncpdp:QuantityUnitOfMeasure'}
    expectedSupplyDuration: {code: d, unit: days, value: 10, system: 'http://unitsofmeasure.org'}
    numberOfRepeatsAllowed: 2
  medicationCodeableConcept:
    text: amoxicillin 400 mg/5 mL oral suspension
    coding:
    - {code: '68115002830', system: 'http://hl7.org/fhir/sid/ndc'}
  resourceType: MedicationRequest
  dosageInstruction:
  - {text: Take 5 mL orally twice daily for 10 days}
  ...
...

medicationCodeableConcept:
  text: amoxicillin 400 mg/5 mL oral suspension
  coding:
    - {code: '68115002830', system: 'http://hl7.org/fhir/sid/ndc'}
dispenseRequest:
  quantity: {code: C48542, value: 150.0, system: 'urn:app:aidbox:e-prescriptions:ncpdp:QuantityUnitOfMeasure'}
  expectedSupplyDuration: {code: d, unit: days, value: 10, system: 'http://unitsofmeasure.org'}
  numberOfRepeatsAllowed: 2
dosageInstruction:
  - {text: Take 5 mL orally twice daily for 10 days}

Set MedicationRequest.dispenseRequest.performer. It should be the pharmacy that initiated the change.

Set MedicationRequest.authoredOn. It should be the date of committing the response.

ApprovedWithChanges

Means the medication was allowed with a change to any included resource/field of the MedicationRequest, except the Patient. It is not recommended to change anything but Medication/MedicationRequest.

Set the decision:

extension:
  - url: >-
      http://aidbox.app/ePrescription/FHIRSchema/medication-request-rx-change-decision
    valueCode: approved-with-changes

Set MedicationRequest.dispenseRequest.performer. It should be the pharmacy that initiated the change.

Set MedicationRequest.authoredOn. It should be the date of committing the response.

Validated

Can only be used for U request type, alongside with denied. When a provider Approves an RxChangeRequest with a MessageRequestCode value of “Provider Authorization” (U) each element being responded to will have a Validated tag and will include the appropriate Response Reason Code and supporting data element. Ex: If NPI was requested, the response will echo back SubCode G, Response reason code GM and will have a populated tag.

NOTE: If multiple data elements were requested, a provider may send a validation response to fewer elements however at least one element must be returned.

In order to understand which fields are requested to populate see the notation below

MessageRequestSubCode values are stored as MedicationRequest extension

...
extension:
  - url: >-
      http://aidbox.app/ePrescription/FHIRSchema/medication-request-rx-change-message-request-sub-codes
    extension:
      - url: subcode
        valueCoding:
          code: A
          system: urn:app:aidbox:e-prescriptions:surescripts:MessageRequestSubCode
      - url: subcode
        valueCoding:
          code: B
          system: urn:app:aidbox:e-prescriptions:surescripts:MessageRequestSubCode
      - url: subcode
        valueCoding:
          code: D
          system: urn:app:aidbox:e-prescriptions:surescripts:MessageRequestSubCode
      - url: subcode
        valueCoding:
          code: F
          system: urn:app:aidbox:e-prescriptions:surescripts:MessageRequestSubCode
      - url: subcode
        valueCoding:
          code: G
          system: urn:app:aidbox:e-prescriptions:surescripts:MessageRequestSubCode
      - url: subcode
        valueCoding:
          code: I
          system: urn:app:aidbox:e-prescriptions:surescripts:MessageRequestSubCode
      - url: subcode
        valueCoding:
          code: M
          system: urn:app:aidbox:e-prescriptions:surescripts:MessageRequestSubCode
...

The following MessageRequestSubCode values can be specified by the pharmacy:

NOTE: ReasonCode values are prefilled for each MessageRequestSubCode value

For example Pharmacy requested to populated the following data:

• StateLicenseNumber (MessageRequestSubCode = A)
• DEANumber (MessageRequestSubCode = B)
• Data2000WaiverID (MessageRequestSubCode = F)
• StateControlSubstanceNumber (MessageRequestSubCode = D)
• CertificateToPrescribe (MessageRequestSubCode = M)
• NPI (MessageRequestSubCode = G)
• Specialty (MessageRequestSubCode = I)

Practitioner resource related fields:

...
identifier:
  - value: MD123456
    type:
      coding:
        - system: http://terminology.hl7.org/CodeSystem/v2-0203
          code: SL
  - value: AB1234563
    type:
      coding:
        - system: http://terminology.hl7.org/CodeSystem/v2-0203
          code: DEA
  - value: XB1234563
    system: urn:app:aidbox:e-prescriptions:ncpdp:Data2000WaiverID
  - value: MA-CS-456789
    system: urn:app:aidbox:e-prescriptions:ncpdp:StateControlSubstanceNumber
  - value: CTP.OH.123456
    system: urn:app:aidbox:e-prescriptions:ncpdp:CertificateToPrescribe
  - value: '9102210835'
    system: http://hl7.org/fhir/sid/us-npi
    type:
      coding:
        - system: http://terminology.hl7.org/CodeSystem/v2-0203
          code: NPI
...

If only an inactive StateLicenseNumber is available, set the use field of the corresponding identifier to "old"

...
  - value: MD123456
    use: old
    type:
      coding:
        - system: http://terminology.hl7.org/CodeSystem/v2-0203
          code: SL
...

PractitionerRole resource related fields:

...
specialty:
  - coding:
      - system: http://nucc.org/provider-taxonomy
        code: 207Q00000X
        display: Family Medicine
    text: Family Medicine
...