Occupational asthma
Asthma - occupational exposure; Irritant-induced reactive airways disease
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.
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 become tight. This reduces the amount of air that can pass through.
Asthma
Asthma is a disease that causes the airways of the lungs to swell and narrow. It leads to wheezing, shortness of breath, chest tightness, and coughi...
In persons 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 and it 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 allergen.
Symptoms usually get worse toward the end of the work week and may go away on weekends or vacations.
Symptoms include:
- Coughing
- Tight feeling in the chest
-
Shortness of breath
Shortness of breath
Breathing difficulty may involve:Difficult breathingUncomfortable breathingFeeling like you are not getting enough air
- Wheezing
Exams and Tests
The health care provider will perform a physical exam and ask about your medical history. Your symptoms may have a pattern of getting worse with a certain workplace environment or substance.
The provider will listen to your lungs with a stethoscope to check for wheezing.
Tests may be ordered to confirm diagnosis:
-
Blood tests to look for
antibodies
to the substance
Antibodies
An antibody is a protein produced by the body's immune system when it detects harmful substances, called antigens. Examples of antigens include micr...
-
Bronchial provocation test (test measuring reaction to the suspected
allergen
)
Allergen
An allergen is a substance that can cause an allergic reaction. In some people, the immune system recognizes allergens as foreign or dangerous. As ...
-
Chest x-ray
Chest x-ray
A chest x-ray is an x-ray of the chest, lungs, heart, large arteries, ribs, and diaphragm.
-
Complete blood count
Complete blood count
A complete blood count (CBC) test measures the following:The number of red blood cells (RBC count)The number of white blood cells (WBC count)The tota...
- Peak expiratory flow rate
-
Pulmonary function tests
Pulmonary function tests
Pulmonary function tests are a group of tests that measure breathing and how well the lungs are functioning.
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 protect or reduce your exposure may help.
Asthma medicines may help manage your symptoms.
Your provider may prescribe:
-
Asthma
quick-relief medicines
, called bronchodilators, to help relax the muscles of your airways.
Quick-relief medicines
Asthma - quick-relief drugs - short-acting beta-agonists; Asthma - quick-relief drugs - bronchodilators; Asthma - quick-relief drugs - oral steroids;...
-
Asthma
control medicines
that are taken every day to prevent symptoms.
Control medicines
Asthma - inhaled corticosteroids; Asthma - long-acting beta-agonists; Asthma - leukotriene modifiers; Asthma - cromolyn; Bronchial asthma-control dru...
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 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.
References
Lemiere C, Vandenplas O. Occupational allergy and asthma. In: Adkinson NF Jr., Bochner BS, Burks AW, et al, eds.
Middleton's Allergy Principles and Practice
. 8th ed. Philadelphia, PA: Elsevier Mosby; 2014:chap 59.
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Spirometry - illustration
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.
Spirometry
illustration
-
Respiratory system - illustration
Air is breathed in through the nasal passageways, travels through the trachea and bronchi to the lungs.
Respiratory system
illustration
-
Spirometry - illustration
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.
Spirometry
illustration
-
Respiratory system - illustration
Air is breathed in through the nasal passageways, travels through the trachea and bronchi to the lungs.
Respiratory system
illustration
Review Date: 4/30/2015
Reviewed By: Laura J. Martin, MD, MPH, ABIM Board Certified in Internal Medicine and Hospice and Palliative Medicine, Atlanta, GA. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the A.D.A.M. Editorial team.