Health Conditions

In many ways, asthma is the result of an overreactive immune system. When the body is first exposed to a foreign substance (called an antigen) the immune system forms antibodies to fight it. The antibodys are shaped so that they fit, like a key into a particular lock, into the molecules on the surface of a particular antigen

In the case of asthma, when the lungs are exposed to an allergen, the immune system forms antibodies that attach to mast cells in the immune system. When there is later exposure to the allergen, these mast cells release inflammatory substances that are intended to protect the body from the allergen.

This causes three changes to occur in the bronchi of an asthmatic. The first change, inflammation or swelling, leads to the next two changes, constriction and sensitivity. During an asthma attack, these three airway changes get worse at the same time and this causes problems because the airways swell on the inside and narrow from the outside. This blocks the flow of air. The tightening of the airways is also called bronchospasm or bronchoconstriction. When they are in this condition, the airways are even more sensitive to animal dander, pollen, tobacco smoke, air pollution, the common cold, or cold air.

When an asthma attack occurs, the airways are constricted, reducing the amount of oxygen absorbed into the blood.

An asthma attack may appear to be mild at first, but it can become significantly more serious. Four to six hours after antigen inhalation, inflammatory cells are lured into the airways by chemicals released earlier. These inflammatory cells release chemical messengers that cause further airway obstruction through constriction, swelling and spasms of the airway. This second wave may last for days or even weeks after the first attack, and can be more severe and more dangerous than the first attack.

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Note: The above information is intended to supplement, not substitute for, the expertise and judgment of your physician, pharmacist, or other healthcare professional. It is not intended to diagnose a health condition, but it can be used as a guide to help you decide if you should seek professional treatment or to help you learn more about your condition once it has been diagnosed.