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Asthma Health Center

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Asthma Triggers - Topic Overview

An asthma trigger is a factor that can lead to sudden difficulty breathing or other symptoms of asthma (asthma attack).

Some triggers are substances a person may be allergic to (allergens). Allergens cause the body's natural defenses (immune system) to produce chemicals called immunoglobulin E (IgE) antibodies. These chemicals bind to allergens, causing inflammation of the bronchial tubes, which carry air to the lungs. The allergen may also cause asthma attacks. These triggers include:

Recommended Related to Asthma

Hypoxia and Hypoxemia

When your body doesn't have enough oxygen, you could get hypoxemia or hypoxia. These are dangerous conditions. Without oxygen, your brain, liver, and other organs can be damaged just minutes after symptoms start. Hypoxemia (low oxygen in your blood) can cause hypoxia (low oxygen in your tissues) when your blood doesn't carry enough oxygen to your tissues to meet your body's needs. The word hypoxia is sometimes used to describe both problems.

Read the Hypoxia and Hypoxemia article > >

Other triggers can cause asthma symptoms without affecting the body's immune system. These include:

    WebMD Medical Reference from Healthwise

    Last Updated: /2, 14 1
    This information is not intended to replace the advice of a doctor. Healthwise disclaims any liability for the decisions you make based on this information.
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