Asthma is a lifelong condition that affects nearly 300 million people across the globe. According to the National Institutes of Health, over 16 million adults and 7 million children in America alone are affected by asthma. This widespread disease is a major cause of childhood disability and has a lifelong impact on a child’s development. The Asthma and Allergy Foundation of America (AAFA) reports that nearly half a million people are admitted to emergency rooms each year due to asthma-related complications. Despite the widespread prevalence of asthma, a great deal remains to be learned about the disease.

Asthma is characterized by respiratory difficulties caused by blocked or narrow airways. The effects are typically temporary and appear in flare-ups known as asthma episodes or asthma attacks. Severe asthma attacks may require emergency medical treatment.

Asthma can be classified into allergic and non-allergic types, both of which are marked by obstruction and inflammation in the airways, according to the AAFA. Allergic asthma is the most common form, and attacks are usually triggered by exposure to particular allergens. Non-allergic asthma accounts for all cases unrelated to allergies. Non-allergic asthma episodes are brought on by irritants like emotional stress, weather or smoke.

In both allergic and non-allergic asthma, the inflamed airways cause a number of uncomfortable and occasionally debilitating symptoms. Inflammation in the airways impairs the lungs’ ability to pump air. Asthma also affects the bronchi — the passageways in which air reaches the lungs. Airflow obstructions in the lungs and bronchi cause coughing, wheezing and a tight chest. The respiratory symptoms may also cause difficulty sleeping. Asthma attacks occur when a trigger causes the airways to tighten and the lining of air passages to swell, constricting the movement of air. Flare-ups are brought on by a number of possible triggers, and the gravity and severity of episodes are different for each individual.

Both genetic and environmental factors contribute to the development of asthma, but the precise cause of the disease is still unclear. While asthma is typically hereditary, the triggers that cause the disease vary from person to person. Allergens that exacerbate asthma include dust mites, pollen and mold. Any substance that causes allergies, whether airborne or not, can also cause an asthma episode. For example, a person allergic to peanut butter may experience an asthma episode in response to the allergen. Non-allergen triggers include cigarettes, wood fires, strong odors like paint fumes or perfume, smog and aerosol spray. Additional factors that can aggravate asthma include: medications, exercise, cold or dry weather and strong emotions that cause unconscious breathing changes. Asthma triggers affect each individual in a different way, and someone may have only one or a few triggers while others are sensitive to a whole litany of irritants.

Asthma usually grows more manageable over time, as people with asthma begin to recognize their triggers and avoid them. Long-term asthma drugs are usually daily medications that reduce inflammation in your respiratory system. For allergic asthma, drugs that treat allergies can also help prevent asthma episodes. When an asthma flare-up does occur, fast-acting medications relax the constricted airways to help air pass through.