Asthma triggers are things that can cause asthma symptoms or an asthma attack. There are many different kinds of asthma triggers. Triggers can be an allergic reaction to allergens that irritate the lungs. The allergens that most commonly trigger asthma are dust mites, animal dander, cockroaches, pollen, grass and the mold alternaria. Common irritants such as vapors, fumes, cigarette smoke, air pollution, perfumes, cleaning products, upper respiratory tract infections, emotions, medications, the weather and physical activity also can trigger asthma attacks. An asthma attack or asthma symptoms also can occur without an allergic reaction.
Exposure to allergens and/or irritants may lead to increased difficulty in breathing during physical activity. Exercise and sports that require long periods of exertion without rest may trigger symptoms. Examples of these types of sports are basketball, soccer, hockey and running. For more information on activities and asthma, see Different Sports/Different Risks.
Students with asthma may be overly sensitive to changes in temperature and humidity, especially cold dry air. Because students tend to breath through their mouths during exertion, cold dry air can reach the lower airways before it is warmed and humidified by the nose. Other triggers include air pollutants, high pollen counts and viral respiratory tract infections.