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Asthma

Asthma is a chronic (long-term) lung disease that inflames and narrows the airways.

PubMed Health Glossary
(Source: NIH - National Heart, Lung, and Blood Institute)

Asthma

Asthma (AZ-ma) is a chronic (long-term) lung disease that inflames and narrows the airways. Asthma causes recurring periods of wheezing (a whistling sound when you breathe), chest tightness, shortness of breath, and coughing. The coughing often occurs at night or early in the morning.

Asthma affects people of all ages, but it most often starts during childhood. In the United States, more than 25 million people are known to have asthma. About 7 million of these people are children.

Overview

To understand asthma, it helps to know how the airways work. The airways are tubes that carry air into and out of your lungs. People who have asthma have inflamed airways. This makes them swollen and very sensitive. They tend to react strongly to certain inhaled substances.

When the airways react, the muscles around them tighten. This narrows the airways, causing less air to flow into the lungs. The swelling... Read more about Asthma

What works? Research summarized

Evidence reviews

Feather versus non‐feather bedding for asthma

An allergen is the substance that causes an allergic reaction in someone who is hypersensitive to it. A major allergen for asthma is the house dust mite. It is thought that artificial (man‐made) fibre fillings for pillows and bedding are less likely to gather allergens than feather‐filled pillows and quilts. However, there is some evidence that in fact, feather bedding may in fact be less likely to cause asthma. The review found no trials comparing feathers with man‐made fibres, and research is needed to be certain which is better for people with asthma.

Intranasal corticosteroids for asthma control in people with coexisting asthma and rhinitis

It has been suggested for nearly twenty years that nasal sprays containing corticosteroids might improve asthma outcomes in people suffering from both asthma and rhinitis. Intranasal corticosteroids had few side effects in people with mild asthma, but the improvements in symptoms scores and lung function could have arisen by chance. Intranasal corticosteroids may be a promising alternative treatment for patients with rhinitis and mild asthma. More research is needed before considering changing the current practice of prescribing corticosteroids delivered by oral inhalers for asthma, and by nasal sprays for rhinitis.

Does reducing the amount of salt in a diet improve asthma symptoms?

A review of the current literature suggests that reduction in the amount of dietary sodium consumed has no significant effect on the symptoms of asthma but may be associated with improvements in some lung function measurements in exercise‐induced asthma.

See all (822)

Summaries for consumers

Feather versus non‐feather bedding for asthma

An allergen is the substance that causes an allergic reaction in someone who is hypersensitive to it. A major allergen for asthma is the house dust mite. It is thought that artificial (man‐made) fibre fillings for pillows and bedding are less likely to gather allergens than feather‐filled pillows and quilts. However, there is some evidence that in fact, feather bedding may in fact be less likely to cause asthma. The review found no trials comparing feathers with man‐made fibres, and research is needed to be certain which is better for people with asthma.

Intranasal corticosteroids for asthma control in people with coexisting asthma and rhinitis

It has been suggested for nearly twenty years that nasal sprays containing corticosteroids might improve asthma outcomes in people suffering from both asthma and rhinitis. Intranasal corticosteroids had few side effects in people with mild asthma, but the improvements in symptoms scores and lung function could have arisen by chance. Intranasal corticosteroids may be a promising alternative treatment for patients with rhinitis and mild asthma. More research is needed before considering changing the current practice of prescribing corticosteroids delivered by oral inhalers for asthma, and by nasal sprays for rhinitis.

Does reducing the amount of salt in a diet improve asthma symptoms?

A review of the current literature suggests that reduction in the amount of dietary sodium consumed has no significant effect on the symptoms of asthma but may be associated with improvements in some lung function measurements in exercise‐induced asthma.

See all (277)

More about Asthma

Photo of a child

Also called: Bronchial asthma, Asthmatic

Other terms to know:
Bronchi, Lungs

Related articles:
How the Lungs Work

Keep up with systematic reviews on Asthma:

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