Skip to content
My WebMD Sign In, Sign Up

Asthma Health Center

Font Size

Asthma in Teens and Adults - Cause

The cause of asthma isn't known. Health experts believe that inherited, environmental, and immune system factors combine to cause inflammation camera.gif of the airways. This can lead to asthma and asthma attacks.

Family history

Asthma may run in families (be inherited). If this is the case in your family, you may be more likely than other people to get long-lasting (chronic) inflammation in the airways.

Immune system

In some people, an allergic reaction causes asthma symptoms. An allergen makes the immune system cells release chemicals that cause inflammation.

Studies show that exposure to allergens such as dust mites, cockroaches, and animal dander may influence asthma's development. Asthma is much more common in people who have allergies. But not all people who have allergies get asthma. And not all those who have asthma have allergies.

Environment

Environmental factors and today's germ-conscious lifestyle may play a role in the development of asthma. Some experts believe that there are more cases of asthma because of pollution and less exposure to certain types of bacteria or infections.1 As a result, children's immune systems may develop in a way that makes it more likely they will also get allergies and asthma.

Asthma in adults also can be related to exposure to substances at work. This is called occupational asthma.

1

WebMD Medical Reference from Healthwise

Last Updated: February 22, 2013
This information is not intended to replace the advice of a doctor. Healthwise disclaims any liability for the decisions you make based on this information.
Next Article:

When Is Your Asthma Worse?

When Is Your Asthma Worse?

Take the WebMD Asthma assessment to get Personalized Action Plan

Start Now

Today on WebMD

Distressed woman
Slideshow
Woman holding an asthma inhaler
Article
 
Get Personalized Asthma Advice
Health Check
asthma overview
Slideshow
 
Los Angeles skyline in smog
Slideshow
man in a field with allergies
Slideshow
 
Woman holding inhaler
VIDEO
Slideshow Allergy Myths and Facts
Slideshow
 
Man outdoors coughing
Article
Lung and bronchial tube graphic
Article
 
10 Worst Asthma Cities
Slideshow
runner
Article