When viewing this topic in a different language, you may notice some differences in the way the content is structured, but it still reflects the latest evidence-based guidance.

Last reviewed: 21 Mar 2025
Last updated: 31 Jul 2024

Summary

Definition

History and exam

Key diagnostic factors

  • presence of risk factors
  • expiratory wheezes
  • dyspnoea
  • cough
  • chest tightness
  • diurnal variability of symptoms
  • episodic symptoms
  • historical record of variable peak expiratory flow (PEF) or FEV₁
  • nasal polyposis
  • recent upper respiratory tract infection

Risk factors

  • family history
  • allergens/irritants
  • atopic disease history
  • cigarette smoking
  • vaping
  • respiratory viral infection early in life
  • nasal polyposis
  • low socioeconomic status
  • obesity
  • gastro-oesophageal reflux
  • obstructive sleep apnoea

Diagnostic investigations

1st investigations to order

  • spirometry (FEV₁/FVC ratio and BDR)
  • peak expiratory flow (PEF)

Investigations to consider

  • CXR
  • FBC with differential
  • fractional exhaled nitric oxide (FeNO)
  • bronchial challenge test
  • allergen testing

Emerging tests

  • sputum eosinophilia

Treatment algorithm

Contributors

Authors

Onyeka Umerah,

Consultant Respiratory Physician

Glenfield Hospital

Leicester

UK

Disclosures

OU declares that she has no competing interests.

Acknowledgements

Dr Onyeka Umerah would like to gratefully acknowledge Dr Lauren E. Eggert, Dr Sourav Majumdar, Dr Irwani Ibrahim, Dr Kay Choong See, Dr Francis Thien, and Dr Catherine Weiler, previous contributors to this topic.

Disclosures

LEE declares that she has conducted sponsored research with Regeneron Pharmaceuticals. SM, II, KCS, FT, and CW declare that they have no competing interests.

Peer reviewers

F. Runa Ali,

Consultant Allergist & Respiratory Physician

Barts Health NHS Trust

London

UK

Disclosures

FRA declares that she has no competing interests.

Laia Castro Salvador,

Severe Asthma & Allergy Specialist Clinical Pharmacist

Barts Health NHS Trust

London

UK

Disclosures

LCS declares that she has no competing interests.

Use of this content is subject to our disclaimer