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:
Other triggers can cause asthma symptoms without affecting the body's immune system. These include:
- Cigarette smoke and air pollution.
- Viral infections, such as colds and influenza, and sinus and other upper respiratory infections.
- Exercise. Many people with asthma have symptoms when they exercise.
- Dry, cold air.
- Medicines, such as aspirin or beta-blockers.
- In adults, hormones, including those involved in pregnancy and menstrual periods (just before or during periods).
- Gastrointestinal reflux disease (GERD). GERD may make asthma worse for some people.
Other Works Consulted
- Guarnieri M, Balmes JR (2014). Outdoor air pollution and asthma. Lancet, 383(9928): 1581–1592. DOI 10.1016/S0140-6736(14)60617-6. Accessed May 6, 2014.