{"uid":"cap_m78ZhTBePSQmwGFSfQaf6","slug":"pen-fast-penicillin-allergy-risk-calculator-60c21fa3","name":"PEN-FAST Penicillin Allergy Risk Calculator","description":"Trubiano 2020 PEN-FAST for patients who already report a penicillin allergy. Three caller-assigned flags: allergy event 5 or fewer years ago (2), anaphylaxis/angioedema or potential SCAR as one criterion (2), treatment required (1). Max 5. Risk: 0 very_low, 1–2 low, 3 moderate, 4–5 high. low_risk_for_testing iff score < 3. Not an allergy diagnosis or delabeling order. magent does not take an allergy history.","url":"https://api.magentlab.com/api/calc/pen_fast","method":"GET","headers":{},"bodySchema":{"type":"object","$schema":"https://json-schema.org/draft/2020-12/schema","required":["input"],"properties":{"input":{"type":"object","required":["type","method"],"properties":{"type":{"type":"string","const":"http"},"method":{"enum":["GET","HEAD","DELETE"],"type":"string"},"headers":{"type":"object","additionalProperties":{"type":"string"}},"queryParams":{"type":"object","required":["five_or_fewer_years_ago","anaphylaxis_angioedema_or_scar","treatment_required"],"properties":{"treatment_required":{"type":"boolean","description":"Treatment required for the allergy episode as assigned by the caller (Trubiano 2020). true scores 1. magent does not take an allergy history."},"five_or_fewer_years_ago":{"type":"boolean","description":"Allergy event 5 or fewer years ago as assigned by the caller (Trubiano 2020). true scores 2. magent does not take an allergy history."},"anaphylaxis_angioedema_or_scar":{"type":"boolean","description":"Anaphylaxis/angioedema or potential SCAR as one 2-point criterion (Trubiano 2020). true scores 2; do not add both phenotypes separately. magent does not take an allergy history."}}}},"additionalProperties":false},"output":{"type":"object","required":["type"],"properties":{"type":{"type":"string"},"example":{"type":"object"}}}}},"responseSchema":null,"example":null,"exampleRequest":null,"tags":["x402"],"displayCostAmount":"0.005","displayCostAsset":"USDC","priceDynamic":false,"priceHint":null,"priceStatus":"priced","priceSource":"probe","requiresHandshake":false,"reviewCount":0,"rating":{"score":"0.00","successRate":"0.00","reviews":0,"stars":null,"state":"unrated"},"availabilityStatus":"unknown","priceObserved":null,"sessionDeposit":null,"pricing":{"kind":"static","summary":"$0.005/call","primary":{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.005","per":"call","confidence":"exact"},"accepted":[{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.005","per":"call","confidence":"exact"}]},"paymentMethods":[{"uid":"pm_-6YcheKaAmMwF_PxFmhsd","protocol":"x402","methodType":"crypto","chain":"base","mode":"charge","costAmount":"0.005","costPer":"request","priority":0,"asset":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","unit":"request","depositMicros":null,"planRef":null}],"brandName":null,"brandSlug":null,"brandBaseUrl":null,"brandDocsUrl":null,"whatItDoes":"Computes the Trubiano 2020 PEN-FAST score (0–5) and risk category for patients with a reported penicillin allergy to guide allergy testing decisions.","exampleAgentPrompt":"My patient has a reported penicillin allergy — the reaction was anaphylaxis that happened 3 years ago and treatment was required. Can you run the PEN-FAST score to see if they're low risk for penicillin allergy testing?","exampleUseCases":[{"title":"Pre-antibiotic allergy triage in hospital","prompt":"I have a hospitalized patient with a documented penicillin allergy — the event was 2 years ago, it was angioedema, and treatment was required. What's their PEN-FAST score and are they low risk for testing?"},{"title":"Outpatient allergy delabeling screening","prompt":"I'm seeing a patient in clinic who says they had a penicillin allergy reaction over 10 years ago with no anaphylaxis or angioedema and no treatment was needed. Run the PEN-FAST calculator for me."},{"title":"Antimicrobial stewardship risk check","prompt":"For antimicrobial stewardship review: the allergy event happened more than 5 years ago, it was not anaphylaxis, angioedema, or a SCAR reaction, and no treatment was required. What's the PEN-FAST risk category?"}],"resultDescription":"Returns the total PEN-FAST score (integer 0–5), a risk category (very_low, low, moderate, or high), and a boolean low_risk_for_testing flag (true if score < 3), indicating whether the patient is a candidate for low-risk penicillin allergy evaluation per the Trubiano 2020 tool.","failureModes":["Missing required query parameters (five_or_fewer_years_ago, anaphylaxis_angioedema_or_scar, treatment_required) returns a 400 error","Non-boolean values for boolean parameters cause validation errors","Payment header missing or insufficient USDC balance returns 402 Payment Required","Caller misclassifies allergy phenotype leading to incorrect score — the API trusts caller-assigned flags and does not validate clinical accuracy"],"whenToPreferThis":"Use this endpoint when you need a fast, validated, structured PEN-FAST risk score for a patient with a reported penicillin allergy and you already have the three binary clinical flags (timing, phenotype severity, treatment required). It is purpose-built for the Trubiano 2020 instrument and returns a machine-readable risk category and testing recommendation flag, making it ideal for clinical decision support workflows, antimicrobial stewardship automation, or pre-prescription allergy screening pipelines.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-09-14T19:04:18.032Z","isFirstParty":false}