Occupational Asthma

  • Medical Author: Irina Petrache, MD
  • Medical Author: Christopher James Huffer, MD
  • Medical Editor: William C. Shiel Jr., MD, FACP, FACR
    William C. Shiel Jr., MD, FACP, FACR

    William C. Shiel Jr., MD, FACP, FACR

    Dr. Shiel received a Bachelor of Science degree with honors from the University of Notre Dame. There he was involved in research in radiation biology and received the Huisking Scholarship. After graduating from St. Louis University School of Medicine, he completed his Internal Medicine residency and Rheumatology fellowship at the University of California, Irvine. He is board-certified in Internal Medicine and Rheumatology.

Asthma Attack Treatment

Quick GuideAsthma: The Anatomy of an Asthma Attack

Asthma: The Anatomy of an Asthma Attack

Occupational asthma facts

  • Asthma is a lung disease characterized by inflammation of the airways and reversible narrowing of the airways, causing shortness of breath, wheezing, chest tightness, and cough.
  • Occupational asthma is asthma that is caused by a specific agent in the workplace.
  • Many different agents can cause occupational asthma.
  • Symptoms can begin immediately with exposure or even years later.
  • Occupational asthma is diagnosed by a thorough history and physical exam, combined with testing of lung function.
  • Treatment mostly involves completely avoiding the offending agent as soon as possible, combined with routine asthma treatments.

What is occupational asthma?

Asthma is a chronic lung disease characterized by reversible inflammation of the airways (bronchi). In asthma, white blood cells infiltrate the walls of the airways, increased mucus accumulates within the airways, and the muscles surrounding the airways tighten (constrict or "twitch"), resulting in an overall narrowing of the airways. This narrowing of the airways is responsible for the shortness of breath, wheezing, and chest tightness patients with asthma experience during their attacks. Occupational asthma is a type of asthma that is caused by exposure to a particular substance in the workplace. Occupational asthma is not the same as previously diagnosed asthma that is worsened by being at work (this condition would be called work-aggravated asthma).

There are two main types of occupational asthma: one type caused by an agent that stimulates the body's immune system that then triggers asthma (immune-mediated); and another where the agent directly irritates the airways (irritant-induced). Immune-mediated occupational asthma typically has a period of time (latency period) between the workplace exposure and the beginning of symptoms. This latency period can be from a few weeks to several years. In contrast, irritant-induced occupational asthma usually causes symptoms immediately after exposure.

A severe form of irritant-induced occupational asthma is called reactive airways dysfunction syndrome (RADS). This is a condition where the patient suffers a single exposure to a very high concentration of a noxious chemical, usually a gas. A person suffering from RADS will have shortness of breath and chest tightness severe enough to seek medical attention within 24 hours of the exposure. After recovery from the initial massive exposure, the patient will likely have airways that remain excessively responsive or "twitchy" to stimuli from the agent that caused the initial symptoms or other agents. Almost all patients with RADS will have excessively responsive airways for three months, and 50% to 60% will still have excessively responsive airways 18 months later.

Medically Reviewed by a Doctor on 4/30/2015

Subscribe to MedicineNet's Allergy and Asthma Newsletter

By clicking Submit, I agree to the MedicineNet's Terms & Conditions & Privacy Policy and understand that I may opt out of MedicineNet's subscriptions at any time.

  • Occupational Asthma - Causes and Risks

    If known, what was the cause of your occupational asthma? Do you work in an environment that puts you at risk?

    Post View 1 Comment
  • Occupational Asthma - Signs and Symptoms

    Please describe the signs and symptoms associated with your occupational asthma.

  • Occupational Asthma - Treatment

    What was the treatment for your occupational asthma?

  • Occupational Asthma - Prevention

    If you've had occupational asthma, how do you prevent a recurrence? Did you leave your job?


Health Solutions From Our Sponsors