Technical standard · interoperability

HL7 FHIR R4 integration

For hospital IT teams: which FHIR resources PharmaDeux reads and writes, which code systems it uses, and how it connects to your institution.

Status

This page documents the interface design. Formal FHIR profiles (StructureDefinition) and an OpenAPI document are not published yet; they are shared with your IT team during the pre-pilot technical review.

Resources and fields

Resource	Fields used	Code system
MedicationRequest	medicationCodeableConcept · dosageInstruction · authoredOn · subject	WHO ATC · UCUM
Observation (laboratory)	code · valueQuantity · effectiveDateTime · interpretation	LOINC · UCUM
Observation (QTc)	code · method · valueQuantity	LOINC 8636-3 · Fridericia (method)
Observation (Tisdale)	code.text · valueInteger · component	text (no standard code)
Patient · Condition · AllergyIntolerance	Read; identifiers are anonymised as data enters the system	ICD-10

Rules

Score and measurement are separate resources: the Tisdale score is never folded into the QTc Observation; it is its own Observation.
LOINC 8636-3 "QT interval corrected" does not fix the correction method; Fridericia is carried as text in method.
Example and test data carry meta.tag HTEST (v3 ActReason "test health data") and cannot pass as a real record.

Example JSON

MedicationRequest · amiodarone 200 mg

{
  "resourceType": "MedicationRequest",
  "id": "example-amiodarone",
  "meta": {
    "tag": [
      {
        "system": "http://terminology.hl7.org/CodeSystem/v3-ActReason",
        "code": "HTEST",
        "display": "test health data"
      }
    ]
  },
  "status": "active",
  "intent": "order",
  "medicationCodeableConcept": {
    "coding": [
      {
        "system": "http://www.whocc.no/atc",
        "code": "C01BD01",
        "display": "amiodarone"
      }
    ],
    "text": "Amiodarone 200 mg tablet"
  },
  "subject": {
    "reference": "Patient/example"
  },
  "authoredOn": "2026-10-12T09:00:00+03:00",
  "dosageInstruction": [
    {
      "text": "200 mg 1×1",
      "timing": {
        "repeat": {
          "frequency": 1,
          "period": 1,
          "periodUnit": "d"
        }
      },
      "doseAndRate": [
        {
          "doseQuantity": {
            "value": 200,
            "unit": "mg",
            "system": "http://unitsofmeasure.org",
            "code": "mg"
          }
        }
      ]
    }
  ]
}

Observation · QTc 485 ms (Fridericia)

{
  "resourceType": "Observation",
  "id": "example-qtc",
  "meta": {
    "tag": [
      {
        "system": "http://terminology.hl7.org/CodeSystem/v3-ActReason",
        "code": "HTEST",
        "display": "test health data"
      }
    ]
  },
  "status": "final",
  "category": [
    {
      "coding": [
        {
          "system": "http://terminology.hl7.org/CodeSystem/observation-category",
          "code": "procedure"
        }
      ]
    }
  ],
  "code": {
    "coding": [
      {
        "system": "http://loinc.org",
        "code": "8636-3",
        "display": "Q-T interval corrected"
      }
    ],
    "text": "QTc (Fridericia)"
  },
  "subject": {
    "reference": "Patient/example"
  },
  "effectiveDateTime": "2026-10-12T09:00:00+03:00",
  "method": {
    "text": "Fridericia formula (QTc = QT / RR^(1/3))"
  },
  "valueQuantity": {
    "value": 485,
    "unit": "ms",
    "system": "http://unitsofmeasure.org",
    "code": "ms"
  }
}

Observation · Tisdale score

{
  "resourceType": "Observation",
  "id": "example-tisdale",
  "meta": {
    "tag": [
      {
        "system": "http://terminology.hl7.org/CodeSystem/v3-ActReason",
        "code": "HTEST",
        "display": "test health data"
      }
    ]
  },
  "status": "final",
  "code": {
    "text": "Tisdale QT prolongation risk score"
  },
  "subject": {
    "reference": "Patient/example"
  },
  "effectiveDateTime": "2026-10-12T09:00:00+03:00",
  "valueInteger": 11,
  "component": [
    {
      "code": {
        "text": "Age ≥68"
      },
      "valueInteger": 1
    },
    {
      "code": {
        "text": "Female"
      },
      "valueInteger": 1
    },
    {
      "code": {
        "text": "Loop diuretic"
      },
      "valueInteger": 1
    },
    {
      "code": {
        "text": "QTc ≥450 ms"
      },
      "valueInteger": 2
    },
    {
      "code": {
        "text": "QT-prolonging drug"
      },
      "valueInteger": 3
    },
    {
      "code": {
        "text": "≥2 QT-prolonging drugs"
      },
      "valueInteger": 3
    }
  ]
}

Examples are generated by the code that builds PharmaDeux's FHIR payloads · fictional data.

Integration architecture

FHIR R4	RESTful API · Subscription (rest-hook)
HL7 v2	MLLP listener · FHIR R4 conversion layer
Authorisation	OAuth 2.0 · SMART on FHIR
Transport	mTLS (mutual TLS)
Access	RBAC · least privilege
Deployment	On-premises (Docker container, isolated virtual machine) · isolated VPC dedicated to the institution · air-gapped network support
Logging	Syslog (RFC 5424) · append-only audit trail

References

1HL7 International. FHIR Release 4 (R4, v4.0.1). https://hl7.org/fhir/R4/
2WHO Collaborating Centre for Drug Statistics Methodology. ATC/DDD Index. https://www.whocc.no/atc_ddd_index/
3Regenstrief Institute. LOINC. https://loinc.org/
4The Unified Code for Units of Measure (UCUM). https://ucum.org/

This page is for information only and is not for clinical decisions. Decisions rest on the product information (SmPC/PIL), current guidelines and the physician's judgement. Last updated: 13 October 2026