Skip to main content
Update Location

My Location

Update your location to show providers, locations, and services closest to you.

Enter a zip code
Or
Select a campus/region

Occupational asthma

Definition

Occupational asthma is a lung disorder in which substances found in the workplace cause the airways of the lungs to swell and narrow. This leads to attacks of wheezing, shortness of breath, chest tightness, and coughing.

Alternative Names

Asthma - occupational exposure; Irritant-induced reactive airways disease

Causes

Asthma is caused by inflammation (swelling) in the airways of the lungs. When an asthma attack occurs, the lining of the air passages swells and the muscles surrounding the airways activate. This makes the airways narrower and reduces the amount of air that can pass through.

Patient Education Video: Asthma

In people who have sensitive airways, asthma symptoms can be triggered by breathing in substances called triggers.

Many substances in the workplace can trigger asthma symptoms, leading to occupational asthma. The most common triggers are wood dust, grain dust, animal dander, fungi, or chemicals.

The following workers are at higher risk:

  • Bakers
  • Detergent manufacturers
  • Drug manufacturers
  • Farmers
  • Grain elevator workers
  • Laboratory workers (especially those working with laboratory animals)
  • Metal workers
  • Millers
  • Plastics workers
  • Woodworkers

Symptoms

Symptoms are usually due to narrowing of the airways and tightening spasms of the muscles lining the airways. This reduces the amount of air that can pass through, which can lead to wheezing sounds.

Symptoms usually occur shortly after you are exposed to the substance. They often improve or go away when you leave work. Some people may not have symptoms until 12 or more hours after being exposed to the trigger.

Symptoms usually get worse toward the end of the work week and may go away on weekends or vacations.

Symptoms include:

Exams and Tests

The health care provider will perform a physical exam and ask about your medical history. The provider will listen to your lungs with a stethoscope to check for wheezing.

Tests may be ordered to confirm the diagnosis:

Treatment

Avoiding exposure to the substance that is causing your asthma is the best treatment.

Measures may include:

  • Changing jobs (though this may be difficult to do)
  • Moving to a different location at the work site where there is less exposure to the substance. This may help, but over time, even a very small amount of the substance can trigger an asthma attack.
  • Using a respiratory device to eliminate or reduce your exposure may help.

Asthma medicines may help manage your symptoms.

Your provider may prescribe:

Outlook (Prognosis)

Occupational asthma may keep getting worse if you continue to be exposed to the substance that is causing the problem, even if medicines improve your symptoms. You may need to change jobs.

Sometimes, symptoms may continue, even when the substance is removed.

In general, the outcome for people with occupational asthma is good. However, symptoms may continue for years after you are no longer exposed in the workplace.

When to Contact a Medical Professional

Call your provider if you have symptoms of asthma.

Talk to your provider about getting the flu and pneumococcal ("pneumonia") vaccines.

If you've been diagnosed with asthma, call your provider right away if you develop a cough, shortness of breath, fever, or other signs of a lung infection, especially if you think you have the flu. Since your lungs are already damaged, it's very important to have the infection treated right away. This will prevent breathing problems from becoming severe, as well as further damage to your lungs.

Gallery

Spirometry
Spirometry is a painless study of air volume and flow rate within the lungs. Spirometry is frequently used to evaluate lung function in people with obstructive or restrictive lung diseases such as asthma or cystic fibrosis.
Coronavirus
Coronaviruses are a family of viruses. Infection with these viruses can cause mild to moderate respiratory illnesses such as the common cold. Some coronaviruses may cause severe illness and lead to pneumonia or even death.

References

Lemière C, Martin JG. Occupational respiratory allergies. In: Rich RR, Fleisher TA, Shearer WT, Schroeder HW, Frew AJ, Weyand CM, eds. Clinical Immunology: Principles and Practice. 5th ed. Philadelphia, PA: Elsevier; 2019:chap 49.

Lemière C, Vandenplas O. Asthma in the workplace. In: Broaddus VC, Ernst JD, King TE, et al, eds. Murray and Nadel's Textbook of Respiratory Medicine. 7th ed. Philadelphia, PA: Elsevier; 2022:chap 100.

Lemière C, Vandenplas O. Occupational allergy and asthma. In: Burks, AW, Holgate ST, O'Hehir RE, et al, eds. Middleton's Allergy: Principles and Practice. 9th ed. Philadelphia, PA: Elsevier; 2020:chap 56.

Tarlo SM. Occupational lung disease. In: Goldman L, Schafer AI, eds. Goldman-Cecil Medicine. 26th ed. Philadelphia, PA: Elsevier; 2020:chap 87.

Last reviewed April 17, 2021 by David C. Dugdale, III, MD, Professor of Medicine, Division of General Medicine, Department of Medicine, University of Washington School of Medicine. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team..

Related specialties

Our experts