Allergy & Adverse Reaction Summary

Overview

Pull all AllergyIntolerance resources for a patient. Categorize by type (drug, food, environmental). Grade severity and criticality. Flag high-risk allergies that require special clinical attention (anaphylaxis history, contrast dye, latex, NSAID sensitivity). Cross-reference against current medications to detect active conflicts. Output a structured summary with actionable safety flags.

FHIR Resources Used

Resource	Purpose	Search Parameters
AllergyIntolerance	Allergy and intolerance records	patient, clinical-status
MedicationRequest	Current medications for conflict detection	patient, status=active
Observation	IgE levels if available	patient, code (LOINC)

Instructions

Step 1: Pull All AllergyIntolerance Resources

code

Tool: fhir_search
resourceType: "AllergyIntolerance"
queryParams: "patient=[patient-id]"

Retrieve all records regardless of clinical status to capture full history. For each entry extract:

•code.coding: Substance (RxNorm for drugs, SNOMED CT for non-drugs)
•clinicalStatus: active, inactive, resolved
•verificationStatus: confirmed, unconfirmed, refuted, entered-in-error
•type: allergy vs intolerance
•category: food, medication, environment, biologic
•criticality: low, high, unable-to-assess
•
reaction[]: Each reaction event
- •manifestation[].coding[].display: What happened (hives, anaphylaxis, rash, etc.)
- •severity: mild, moderate, severe
- •onset: When the reaction occurred
- •substance: Specific substance if different from the top-level code
•onsetDateTime: When allergy was first identified
•recorder: Who documented it
•note: Free-text notes

Step 2: Categorize Allergies

Group into four categories:

Drug Allergies (category = "medication"):

•Identify drug class from the substance code or name
•Check for class-level allergies vs specific drug allergies
•Note if the allergy is to a drug class (e.g., "penicillins") vs specific drug (e.g., "amoxicillin")

Food Allergies (category = "food"):

•Common: peanuts, tree nuts, shellfish, milk, eggs, wheat, soy, fish
•Note severity -- food allergies with anaphylaxis history are high-risk

Environmental Allergies (category = "environment"):

•Pollen, dust mites, mold, animal dander, insect venom
•Usually lower clinical urgency unless anaphylaxis to insect stings

Biologic/Other (category = "biologic" or uncategorized):

•Latex, contrast dye, blood products, vaccines

Step 3: Flag High-Risk Allergies

Scan the allergy list for the following high-risk patterns:

Anaphylaxis History:

•Any allergy where reaction[].manifestation includes SNOMED 39579001 (Anaphylaxis) or display text contains "anaphylaxis" or "anaphylactic"
•Flag with: "ANAPHYLAXIS RISK -- Ensure epinephrine availability"

Contrast Dye Allergy:

•Substance code or display contains "iodine", "contrast", "iodinated contrast"
•Flag with: "CONTRAST ALLERGY -- Premedication protocol required for CT with contrast"

Latex Allergy:

•Substance = SNOMED 111088007 (Latex) or display contains "latex"
•Flag with: "LATEX ALLERGY -- Use non-latex gloves and equipment"
•Check for cross-reactive foods: banana, avocado, kiwi, chestnut

NSAID Sensitivity:

•Allergy to aspirin, ibuprofen, naproxen, or "NSAIDs" as a class
•Flag with: "NSAID SENSITIVITY -- Avoid all COX inhibitors. Consider acetaminophen as alternative."
•Check for aspirin-exacerbated respiratory disease (Samter's triad): NSAID allergy + asthma + nasal polyps

Sulfonamide Allergy:

•Allergy to "sulfa", "sulfamethoxazole", "trimethoprim-sulfamethoxazole", or sulfonamide antibiotics
•Note: Sulfonamide antibiotic allergy does NOT contraindicate non-antibiotic sulfonamides (furosemide, thiazides, celecoxib) -- cross-reactivity is negligible but document awareness

Opioid Allergy:

•If allergy to one opioid, check if it is a true allergy (e.g., anaphylaxis) or a side effect misclassified as allergy (nausea, itching are common opioid side effects, not allergies)
•Flag specific opioid vs opioid class

Step 4: Check Cross-Reactivity Patterns

Apply known cross-reactivity rules:

Penicillin Cross-Reactivity:

•Penicillin allergy -> ~2% cross-reactivity with cephalosporins (1st gen > 2nd gen > 3rd gen)
•Penicillin allergy -> ~1% cross-reactivity with carbapenems
•If penicillin allergy with anaphylaxis: avoid all beta-lactams pending allergy testing
•If penicillin allergy with mild rash only: cephalosporins (2nd gen+) generally safe

Cephalosporin Cross-Reactivity:

•1st gen cephalosporins (cephalexin, cefazolin) have highest cross-reactivity with penicillin
•Cross-reactivity is side-chain dependent, not ring-structure dependent (current evidence)

ACE Inhibitor Angioedema:

•ACE inhibitor-induced angioedema -> contraindication to all ACE inhibitors
•ARBs are generally safe alternatives (low cross-reactivity)
•Document as a separate allergy entry if not already present

Statin Myopathy:

•Myopathy/rhabdomyolysis with one statin does not necessarily contraindicate all statins
•Hydrophilic statins (rosuvastatin, pravastatin) may be tolerated

Step 5: Cross-Reference with Active Medications

code

Tool: fhir_search
resourceType: "MedicationRequest"
queryParams: "patient=[patient-id]&status=active"

For each active medication, check against the allergy list:

•Direct match: medication name/code matches allergy substance
•Class match: medication belongs to same drug class as allergy substance
•Cross-reactivity match: medication has known cross-reactivity with allergy substance

Flag any active conflict as:

code

ACTIVE CONFLICT: Patient is on [medication] but has documented allergy to [substance]
Reaction history: [manifestation] - Severity: [severity]
Action required: Verify with prescriber. This may be a monitored override or a documentation error.

Step 6: Assess Documentation Quality

Flag documentation issues:

•Allergy with no reaction documented (reaction array empty)
•Allergy with no severity specified
•verificationStatus = "unconfirmed" for allergies older than 1 year (should be confirmed or refuted)
•type not specified (allergy vs intolerance distinction missing)
•No allergies documented AND no "No Known Allergies" entry (allergy status unknown vs NKDA)

Step 7: Format Output

code

ALLERGY & ADVERSE REACTION SUMMARY
====================================
Patient: [name] ([patient-id])
Reviewed: [timestamp]
Total Entries: [count]
Allergy Status: [Reviewed / Not Reviewed / NKDA]

HIGH-RISK ALERTS
================
[!] ANAPHYLAXIS RISK: [substance] - ensure epinephrine access
[!] CONTRAST ALLERGY: Premedication required
[!] LATEX ALLERGY: Non-latex equipment required
[!] ACTIVE CONFLICT: On [medication] with allergy to [substance]

DRUG ALLERGIES
==============
1. [Substance] (RxNorm: [code])
   Type: Allergy | Status: Active | Criticality: High
   Reaction: [manifestation] | Severity: Severe
   Cross-reactivity note: [if applicable]
   Documented: [date] by [recorder]
2. ...

FOOD ALLERGIES
==============
1. [Substance] - Reaction: [manifestation] - Severity: [severity]
2. ...

ENVIRONMENTAL ALLERGIES
=======================
1. [Substance] - Reaction: [manifestation] - Severity: [severity]
2. ...

INTOLERANCES (Non-Allergic)
============================
1. [Substance] - Type: Intolerance - Reaction: [manifestation]
2. ...

DOCUMENTATION QUALITY
=====================
- [N] allergies missing reaction details
- [N] allergies with unconfirmed verification status
- [Notes on documentation gaps]

CROSS-REACTIVITY NOTES
=======================
- [Relevant cross-reactivity information based on documented allergies]

Examples

Example 1: Patient With Multiple Drug Allergies

User says: "Check allergies for patient 33221"

Actions:

•fhir_search AllergyIntolerance?patient=33221 -- returns 5 entries
•fhir_search MedicationRequest?patient=33221&status=active -- returns 8 medications

Result:

code

ALLERGY & ADVERSE REACTION SUMMARY
====================================
Patient: David Park (33221)
Reviewed: 2026-02-07T10:00:00Z
Total Entries: 5
Allergy Status: Reviewed

HIGH-RISK ALERTS
================
[!] ANAPHYLAXIS RISK: Penicillin - ensure epinephrine access
[!] ACTIVE CONFLICT: On cephalexin (Keflex) with documented penicillin allergy
    (anaphylaxis history) - IMMEDIATE REVIEW REQUIRED

DRUG ALLERGIES
==============
1. Penicillin (RxNorm: 7980)
   Type: Allergy | Status: Active | Criticality: High
   Reaction: Anaphylaxis | Severity: Severe
   Cross-reactivity: 2% risk with cephalosporins. Given anaphylaxis history,
   avoid all beta-lactams pending formal allergy testing.
   Documented: 2019-05-12

2. Codeine (RxNorm: 2670)
   Type: Intolerance | Status: Active | Criticality: Low
   Reaction: Nausea, vomiting | Severity: Mild
   Note: Likely opioid side effect, not true allergy. Other opioids
   may be tolerated. Consider reclassifying as intolerance if not already.
   Documented: 2020-08-03

FOOD ALLERGIES
==============
1. Shellfish (SNOMED: 278840001)
   Reaction: Urticaria, throat tightness | Severity: Moderate
   Note: Monitor for iodinated contrast cross-reactivity (historically
   cited but evidence is weak; shellfish allergy is protein-based,
   not iodine-based)

ENVIRONMENTAL ALLERGIES
=======================
1. Dust mites (SNOMED: 260147004)
   Reaction: Rhinitis | Severity: Mild

INTOLERANCES
============
1. Lactose (SNOMED: 782415009)
   Type: Intolerance | Reaction: Bloating, diarrhea | Severity: Mild

DOCUMENTATION QUALITY
=====================
- Codeine entry classified as "allergy" but reaction pattern suggests intolerance
- Dust mite allergy missing severity in FHIR record (inferred as mild from manifestation)

Example 2: No Allergies Documented -- Ambiguous Status

User says: "Does patient 99001 have any allergies?"

Actions:

•fhir_search AllergyIntolerance?patient=99001 -- returns 0 entries

Result:

code

ALLERGY & ADVERSE REACTION SUMMARY
====================================
Patient: Lisa Chen (99001)
Reviewed: 2026-02-07T10:15:00Z
Total Entries: 0
Allergy Status: ** NOT REVIEWED **

HIGH-RISK ALERTS
================
[!] ALLERGY STATUS UNKNOWN: No allergy records found. This does NOT mean
    "No Known Allergies" -- it means allergies have never been documented.
    Allergy history MUST be collected before prescribing.

RECOMMENDATION
==============
Ask the patient about:
1. Drug allergies (especially antibiotics, NSAIDs, anesthetics)
2. Food allergies
3. Environmental allergies
4. Latex sensitivity
5. Contrast dye reactions
6. Previous adverse drug reactions

If patient reports no allergies, document a "No Known Allergies" entry:
  Tool: fhir_create
  resourceType: "AllergyIntolerance"
  resource: {
    "clinicalStatus": {"coding": [{"system": "http://terminology.hl7.org/CodeSystem/allergyintolerance-clinical", "code": "active"}]},
    "verificationStatus": {"coding": [{"system": "http://terminology.hl7.org/CodeSystem/allergyintolerance-verification", "code": "confirmed"}]},
    "code": {"coding": [{"system": "http://snomed.info/sct", "code": "716186003", "display": "No known allergy"}]},
    "patient": {"reference": "Patient/99001"}
  }

Troubleshooting

AllergyIntolerance Uses Free Text Instead of Coded Substances

•Some EHR systems populate code.text but not code.coding. Use the display text for matching.
•Attempt fuzzy matching against known drug names and classes for cross-reference purposes.
•Flag these entries for coding improvement: "Allergy to [free text] should be coded with RxNorm/SNOMED for interoperability."

Medication Conflict Detected But May Be Intentional Override

•Clinicians sometimes prescribe medications despite documented allergies after risk-benefit analysis (e.g., penicillin allergy but documented tolerance to amoxicillin after skin testing).
•Check for note or extension fields that indicate a deliberate override.
•Present the conflict but note: "This may be a monitored override. Verify with the prescribing clinician before recommending discontinuation."

AllergyIntolerance Resources Have verificationStatus = "entered-in-error"

•Exclude these from the active summary entirely.
•If the user specifically asks about historical or retracted allergies, include them in a separate "Retracted Entries" section.

Related Skills

•patient-demographics-summary -- for complete patient overview including insurance and contacts
•problem-list-review -- for cross-referencing allergies with conditions
•clinical-summary-generator -- for allergies in the context of a full CCD summary