NSAID Hypersensitivity Classification & Management

Classifies NSAID hypersensitivity by phenotype using the EAACI/Kowalski framework (cross-reactive respiratory N-ERD, cross-reactive cutaneous NECD/NIUA, selective single-drug reaction) and sequences management per each mechanism.

Evidence tier: Guideline-derived.

Decision points

  • What organ system(s) were involved?

Do-not-miss pitfalls

  • Do not confuse cross-reactive NSAID reactions (pharmacological, ≥2 classes) with selective reactions (immunological, one drug/class), the management strategy is opposite.
  • Do not restrict ALL NSAIDs when a patient has had a selective single-drug reaction, other NSAID classes are likely safe and a supervised challenge should be offered.
  • Do not perform aspirin desensitization in uncontrolled asthma or with FEV₁ <70% predicted, this is a hard contraindication.
  • Do not use diphenhydramine alone to manage anaphylaxis from NSAID, it does not reverse bronchospasm or distributive shock; epinephrine is first-line.
  • Do not rely on negative NSAID IgE testing to clear a COX-1 NSAID in a cross-reactive patient, the mechanism is pharmacological, not IgE-mediated.
  • Do not prescribe acetaminophen >1000 mg/dose in N-ERD, partial COX-1 inhibition at higher doses can trigger reactions.
  • Do not conflate N-ERD with aspirin allergy, it is a distinct pharmacological syndrome driven by COX-1 inhibition, not an allergy, and aspirin desensitization can restore tolerance.
  • Do not assume NSAID challenge is the same as desensitization, a single challenge dose documents the phenotype; desensitization is an in-hospital multi-step protocol requiring specialist supervision.

Evidence & citations

  1. Kowalski ML, Asero R, Bavbek S, et al. Classification and practical approach to the diagnosis and management of hypersensitivity to nonsteroidal anti-inflammatory drugs. Allergy. 2013;68(10):1219-1232. PMID 24117484
  2. Kowalski ML, Agache I, Bavbek S, et al. Diagnosis and management of NSAID-Exacerbated Respiratory Disease (N-ERD), an EAACI position paper. Allergy. 2019;74(1):28-39. PMID 30216468
  3. White AA, Stevenson DD. Aspirin-Exacerbated Respiratory Disease. N Engl J Med. 2018;379(11):1060-1070. PMID 30207919
  4. Khan DA, Banerji A, Blumenthal KG, et al. Drug allergy: a 2022 practice parameter update. J Allergy Clin Immunol. 2022;150(6):1333-1393. PMID 36122788

Clinician decision support. Verify against the cited source. Not a substitute for clinical judgment. 100% on-device; no patient data is stored or transmitted.