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Occupational asthma

Last reviewed: 23 Jul 2025
Last updated: 15 Aug 2025

Summary

Definition

History and exam

Key diagnostic factors

  • occupational exposure to sensitizing agents or irritants
  • symptoms of asthma that improve during holidays
  • initial onset of asthma symptoms during a work period
Full details

Risk factors

  • high-level exposure to sensitizer
  • atopy
  • genetic factors
  • smoking
Full details

Diagnostic tests

1st tests to order

  • spirometry
  • chest x-ray
  • skin prick testing (SPT)
  • nonspecific bronchial hyper-responsiveness (NSBHR)
  • serial peak expiratory flow (PEF)
Full details

Tests to consider

  • specific serum IgE assay
  • specific inhalation challenge (SIC)
Full details

Emerging tests

  • induced sputum cytology
  • fractional exhaled nitric oxide (FeNO)

Treatment algorithm

ACUTE

sensitizer-induced

irritant-induced

ONGOING

symptomatic asthma

Contributors

Authors

Ryan Hoy, MB BS, MOEH, FRACP
Ryan Hoy

Respiratory Physician

The Alfred Hospital

Melbourne

Victoria

Australia

Disclosures

RH is an author of a reference cited in the topic.

Susan M. Tarlo, MB BS FRCP(C)
Susan M. Tarlo

Professor of Medicine

University of Toronto

Respiratory Physician

Toronto Western Hospital

Toronto

Ontario

Canada

Disclosures

SMT has received grant support from the Ontario Workplace Safety and Insurance Board (WSIB) and the Centre for Research Expertise in Occupational Disease (funded by Ontario Ministry of Labour). She has acted as a consultant for the Ontario Workplace Safety and Insurance Appeals Tribunal (WSIAT) and has provided clinical case assessments for WSIB. She has been a member of Task Forces for the European Academy of Allergy, Asthma and Clinical Immunology and an expert advisor to a committee of the European Respiratory Society. She is a member of the Occupational Disease Committee of the American Academy of Allergy, Asthma and Clinical Immunology (AAAAI). She has been an invited speaker at meetings of AAAAI and the American Thoracic Society. She is a coeditor of Current Opinion in Allergy and Clinical Immunology, and has received book royalties as coeditor of Asthma in the Workplace. SMT is an author of references cited in the topic.

Peer reviewers

Ware Kuschner, MD

Associate Professor of Medicine

Stanford University

Stanford

Staff Physician

US Department of Veterans Affairs

Palo Alto Health Care System

Palo Alto

CA

Disclosures

WK declares that he has no competing interests.

Karin Pacheco, MD

Associate Professor of Medicine

National Jewish Medical Centre

Denver

CO

Disclosures

KP declares that she has no competing interests.

Philip Harber, MD

Professor of Medicine

University of California

Los Angeles

CA

Disclosures

PH declares that he has no competing interests.

References

Our in-house evidence and editorial teams collaborate with international expert contributors and peer reviewers to ensure that we provide access to the most clinically relevant information possible.

Key articles

Barber CM, Cullinan P, Feary J, et al. British Thoracic Society clinical statement on occupational asthma. Thorax. 2022 May;77(5):433-42.Full text  Abstract

Tarlo SM, Balmes J, Balkissoon R, et al. Diagnosis and management of work-related asthma: American College Of Chest Physicians Consensus statement. Chest. 2008 Sep;134(3 suppl):1S-41S. Abstract

Baur X, Sigsgaard T, Aasen TB, et al. Guidelines for the management of work-related asthma. Eur Respir J. 2012 Mar;39(3):529-45.Full text  Abstract

Global Initiative for Asthma (GINA). Global strategy for asthma management and prevention. May 2025 [internet publication].Full text

American College of Radiology. ACR appropriateness criteria: occupational lung diseases. 2019 [internet publication].Full text

Reference articles

A full list of sources referenced in this topic is available to users with access to all of BMJ Best Practice.
  • Occupational asthma images
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    • Coincidental nonoccupational asthma
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  • Guidelines

    • Global strategy for asthma management and prevention
    • Asthma: diagnosis, monitoring and chronic asthma management (BTS, NICE, SIGN)
    More Guidelines
  • Patient information

    Asthma in adults

    More Patient information
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