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💊 SULF-FAST Sulfa Antibiotic Allergy Rule

UseWhen to use: sulfa-antibiotic allergy labels when delabeling or stewardship challenge is considered.

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StrataScore <3 → low risk; supervised DOC may be appropriate per protocol. ≥3 → allergy evaluation.

LimitsWhen not to use: recent anaphylaxis or SCAR — specialist only. · Pitfall: equating non-antibiotic sulfonamides (e.g. some diuretics) w… · Follow local allergy pathways.

SourceWaldron JL, et al. JAMA Netw Open 2023 (SULF-FAST)

Runs locally in your browser (no PHI uploaded). For licensed clinicians — not a substitute for clinical judgement.
Stored on this device for revisit reminders

This-shift next steps

After scoring: open the scene pack, peer scores, and the matching pathway. Local reference — no HIS write.

Score + version; reference only — not a substitute for care · no HIS write

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Methodology · worked example, guidelines & full notes
Clinical takeaway

PEN-FAST adapted.

When to use

When to use: sulfa-antibiotic allergy labels when delabeling or stewardship challenge is considered.

How it works

≤5 years or unknown (2) + anaphylaxis/angioedema or SCAR (2) + treatment required or unknown (1). 0–5.

Key points

  • PEN-FAST adapted.
  • <3 low risk.
  • Next: PEN-FAST / allergy clinic.

References

Worked calculation

The values below come from this tool's own example placeholders and are computed server-side with the formula shown on this page, so the arithmetic can be checked quickly. It demonstrates how to substitute values only — it is not clinical advice and not a real case.

Five years or less since reaction (or unknown timing)No — >5 y ago (0)
Anaphylaxis / angioedema OR severe cutaneous adverse reaction (SCAR)No (0)
Treatment required for the reaction (or unknown)No (0)

→SULF-FAST0/5

  • Band:Low risk (<5% published) — supervised DOC often considered
  • Cutoff:<3 low risk
Five years or less since reaction (or unknown timing)Yes / unknown (2)
Anaphylaxis / angioedema OR severe cutaneous adverse reaction (SCAR)Yes (2)
Treatment required for the reaction (or unknown)Yes / unknown (1)

→SULF-FAST5/5

  • Band:Elevated risk (≥3) — allergy evaluation preferred
  • Cutoff:<3 low risk
Verification & sources · governance
FAQ

Frequently asked questions

Does SULF-FAST Sulfa Antibiotic Allergy Rule upload patient data? Where is it calculated?
Calculation runs locally in the browser; inputs and results are not uploaded. For licensed clinicians only; interpret with history, investigations and local protocols — not a diagnosis or prescription.
How is SULF-FAST Sulfa Antibiotic Allergy Rule calculated in practice? Can you show a worked example?
Inputs: Five years or less since reaction (or unknown timing) No — >5 y ago (0), Anaphylaxis / angioedema OR severe cutaneous adverse reaction (SCAR) No (0), Treatment required for the reaction (or unknown) No (0) → Result: SULF-FAST 0 /5(Band: Low risk (<5% published) — supervised DOC often considered, Cutoff: <3 low risk) Inputs: Five years or less since reaction (or unknown timing) Yes / unknown (2), Anaphylaxis / angioedema OR severe cutaneous adverse reaction (SCAR) Yes (2), Treatment required for the reaction (or unknown) Yes / unknown (1) → Result: SULF-FAST 5 /5(Band: Elevated risk (≥3) — allergy evaluation preferred, Cutoff: <3 low risk)
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