Asthma

Asthma is not caused by smoking.

The reason asthma develops in one person and not another is not well known. Asthma tends to run in families, but not always.

People with asthma have extra-sensitive airways that overreact to certain environmental elements such as:

• pollens
• fungus
• molds
• animal secretions
• house dust mites
• cold air, etc.

When the airways are exposed to these stimuli, the linings of the airways react by becoming inflamed and swollen. They become "twitchy," meaning that the muscles surrounding the airways tighten and cause the airways to narrow.

Asthma is characterized by episodes of shortness of breath (SOB), tightness in the chest, wheezing and cough, or a combination of the above.

"Pure" asthma can be treated effectively because the changes to the airways can be reversed in most instances. However, if there is a component of emphysema or chronic bronchitis to the asthma condition, the changes cannot be reversed.

For more information about asthma, please refer to the Canadian Lung Association Asthma Resource Center.