Asthma FAQs

Asthma Cities Slideshow

• What is asthma?
• What causes asthma?
• Who gets asthma?
• What is an asthma attack like?
• What is the difference between allergies and asthma?
• What are the effects of asthma?
• When should someone seek medical care?
• Can asthma be cured?
• What are medications for asthma?
• Can asthma attacks be prevented?
• For More Information
• Web Links
• Synonyms and Keywords
• References
• Authors and Editors
• Pictures of Asthma Cities - Slideshow

What is asthma?

Asthma is a disease that affects the breathing passages, or airways, of the lungs. Asthma is a chronic (ongoing, long-term) inflammatory disease that causes difficulty breathing.

When an exacerbation or "attack" of asthma takes place, the inflammation in the airways causes the lining of the breathing passages to swell. This swelling narrows the diameter of the airway, eventually to a point where it is hard to exchange enough air to breathe comfortably. This is when coughing, wheezing, and the sensation of distress start.

There are three "levels" of asthma.

• With mild asthma, symptoms occur no more than twice a week (with nighttime attacks no more than twice a month). The attacks don’t last long, and they are alleviated quickly with medication. There are no symptoms between attacks.
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• With moderate asthma, symptoms occur almost every day and require an inhaler almost every time an attack occurs for symptom relief.
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• With severe asthma, symptoms are present most of the day every day. They restrict activity, and they have often necessitated a hospital stay.

There are also several types of asthma.

• Adult-onset asthma develops after age 20. It is less common than asthma in children, and it affects more women than men.
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• Exercise-induced asthma involves symptoms that occur about 5-20 minutes after beginning an exercise that involves breathing through the mouth. Sports and games that require continuous activity or that are played in cold weather (for example, long-distance running, hockey, soccer, and cross-country skiing) are the most likely to trigger an asthma attack. Other physical exertions that can trigger an attack include laughing, crying, and hyperventilating.
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• Occupational asthma occurs in response to a trigger in the workplace. These triggers include contaminants and allergens in the air and extremes of temperature or humidity.
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• Nocturnal asthma occurs between midnight and 8 am. It is triggered by allergens in the home such as dust and pet dander or is caused by sinus conditions.