Alternative Names

Bronchial asthma; Exercise-induced asthma

Definition of Asthma

Asthma is an inflammatory disorder of the airways, which causes attacks of , shortness of breath, chest tightness, and coughing.

Causes, incidence, and risk factors

Asthma is caused by inflammation in the airways. When an asthma attack occurs, the muscles surrounding the airways become tight and the lining of the air passages swells. This reduces the amount of air that can pass by.


Most people with asthma have attacks separated by symptom-free periods. Some people have long-term shortness of breath with episodes of increased shortness of breath. Either wheezing or a cough may be the main symptom.

Signs and tests

Allergy testing may be helpful to identify allergens in people with persistent asthma. Common allergens include:


The goal of treatment is to avoid the substances that trigger your symptoms and control airway inflammation. You and your doctor should work together as a team to develop and carry out a plan for eliminating asthma triggers and monitoring symptoms.

Expectations (prognosis)

There is no cure for asthma, although symptoms sometimes improve over time. With proper self management and medical treatment, most people with asthma can lead normal lives.


Neil K. Kaneshiro, MD, MHA, Clinical Assistant Professor of Pediatrics, University of Washington School of Medicine. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc. – 7/14/2010

Normal versus asthmatic bronchiole
Peak flow meter
Asthmatic bronchiole and normal bronchiole
Common asthma triggers
Exercise-induced asthma
Respiratory system
Spacer use - series
Metered dose inhaler use - series
Nebulizer use - series
Peak flow meter use - series

ADAM Medical Encyclopedia

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