Asthma triggers vary with asthma types. Asthma triggers are substances of conditions that can provoke asthma symptoms. Though people with asthma may have a number of different triggers, people with different types of asthma may be more susceptible to related triggers.

People with allergic asthma are often sensitive to environmental allergens. Common allergens that can be asthma triggers are mold, dust mites, pet dander, pollen, allergens from cockroaches, smoke, chemicals, and pollutants. Young children with asthma are the most affected by tobacco smoke. This sensitivity has been documented in research, though older children and adults seem less effected by smoke.

Sulfites in food and medication can trigger allergic asthma. Humidity can be problematic for people with allergic asthma since it increases the body’s need for oxygen and fosters the growth of mold. If a person with allergic asthma is aware of their triggers, they should try to avoid exposure to their triggers as much as possible.

The main trigger for exercise-induced asthma is mouth breathing. The clear cause for this trigger is not completely understood. Ways to reduce asthma symptoms during exercise are to avoid exertion, warm up before exercise, and gradually cool down after exercise.

Nighttime or nocturnal asthma may be triggered by prolonged exposure to indoor allergens and being in a reclined position. Nighttime asthma is sometimes called sleep-related asthma. The circadian rhythms, sleep-wake cycles, are thought to trigger asthma symptoms in people with nighttime asthma. Certain body changes such as changes in body temperature and less circulation of adrenal hormones during sleep may trigger asthma symptoms. Delayed reactions to daytime exposure to allergens, allergens in the bedroom, problems with the sinuses, and gastroesophageal reflux disease may be triggers for nocturnal asthma.

Occupational asthma is an asthma type related to triggers found in the workplace. People who work with irritating chemicals or animals are at high risk for occupational asthma. If people who work with chemicals or animals carry allergens on their body or clothing, they may expose family members to these allergens from the workplace. In some cases, a family member will develop asthma to these allergens introduced into the home this way.

Bacterial and viral infections can be a trigger for any of the asthma types. When someone with asthma has a cold, the flu, or a respiratory infection, their asthma symptoms are often much worse. Emotional stress can also be a trigger for any type of asthma.