Clinical Resources

Allergies

Overview

The Allergies page captures information about substances that may trigger adverse reactions in patients. This includes medications, foods, environmental triggers, and other allergens. Recording allergies accurately is critical for patient safety, clinical decision-making, and preventing adverse events during care delivery.

Clinical Data in Source Documents

Allergy information is typically documented in sections like Problem List, History, or Clinical Notes in PDFs or C-CDAs. The data may appear as:

• Narrative lists describing substances and reactions (e.g., “Patient reports swelling with penicillin”).
• Tabular formats in structured C-CDAs with fields for allergen name, reaction, and severity.
• Embedded notes in assessment or medication sections referencing allergic reactions.

Since source documents are often unstructured, allergies may appear inconsistently, requiring careful parsing to identify the allergen, reaction type, and severity.

JSON Output

The platform extracts allergy information into a standardized JSON structure for clear, machine-readable representation:

Key fields:

• Name: The allergen or substance causing the reaction.
• Reaction: Describes the physiological response (e.g., rash, palpitations).
• Severity: Categorizes the intensity of the reaction (mild, moderate, severe).

This structured output enables consistent integration into EHRs, clinical decision-support systems, and analytics tools, allowing providers to act on allergy information efficiently.

{
  "allergies": [
    {
      "name": "Penicillin",
      "reaction": "Rash",
      "severity": "Moderate",
      "page_number": 1
    }
  ]
}

FHIR Output

Extracted allergies are mapped to the FHIR AllergyIntolerance resource for interoperability. Key mappings include:

• Allergen Name → AllergyIntolerance.code.text – Represents the substance causing the reaction.
• Reaction → AllergyIntolerance.reaction.manifestation.text – Describes the observed response.
• Severity → AllergyIntolerance.reaction.severity – Indicates the intensity of the reaction.
• Clinical Status → AllergyIntolerance.clinicalStatus – Typically set to active for ongoing allergies.
• Verification Status → AllergyIntolerance.verificationStatus – Usually set to confirmed to indicate that the allergy has been validated.
• Type → AllergyIntolerance.type – Typically set as allergy.
• Patient Reference → AllergyIntolerance.patient – Links the record to the associated patient.
• Recorded Date → AllergyIntolerance.recordedDate – Captures when the allergy was documented.
• Encounter Reference → AllergyIntolerance.encounter – Associates the allergy record with a specific clinical encounter.

{
  "fullUrl": "urn:uuid:5f4ba677-033e-41bc-8b59-887969258463",
  "resource": {
    "resourceType": "AllergyIntolerance",
    "clinicalStatus": {
      "coding": [
        {
          "system": "http://terminology.hl7.org/CodeSystem/allergyintolerance-clinical",
          "code": "active",
          "display": "Active"
        }
      ]
    },
    "verificationStatus": {
      "coding": [
        {
          "system": "http://terminology.hl7.org/CodeSystem/allergyintolerance-verification",
          "code": "confirmed",
          "display": "Confirmed"
        }
      ]
    },
    "type": {
      "coding": [
        {
          "system": "http://hl7.org/fhir/allergy-intolerance-type",
          "code": "allergy"
        }
      ],
      "text": "Allergy"
    },
    "code": {
      "text": "Penicillin"
    },
    "patient": {
      "reference": "Patient/b17aaab1-311c-4d98-9c93-030277d0aeb0"
    },
    "recordedDate": "2020-01-01",
    "criticality": "low",
    "reaction": [
      {
        "manifestation": [
          {
            "concept": {
              "text": "Rash"
            }
          }
        ],
        "severity": "moderate"
      }
    ],
    "id": "5f4ba677-033e-41bc-8b59-887969258463"
  }
}