As asthma is a common disease, most people are aware that it is a condition that affects the lungs. Asthma is a chronic illness—once a person has it, they will have it throughout their life, through periods of remission where they are asymptomatic do occur.
The main symptoms of asthma are coughing, chest tightness, wheezing (a whistling sound when exhaling), and dyspnea—also known as shortness of breath.
What Causes Asthma Symptoms?
The cause of asthma itself is not known, but it is thought to have environmental and genetic causes .
Asthma symptoms are caused by inflammation and constriction in the airways of the lungs. Underlying inflammation is continuously present in asthma that is not treated —the combination of inflammation and constriction of the muscles surrounding the airways causes airways to narrow, making it more difficult to breathe. During an asthma attack or flare-up, this muscle constriction and production of extra mucus further narrows airways, causing asthma symptoms. 
What Triggers Asthma Symptoms?
Asthma symptoms are caused by exposure to what are called “triggers.” Triggers fall into two categories: allergic (or extrinsic) and non-allergic (or intrinsic).  Asthma triggers are individual to each person, so what triggers one person’s asthma may not be an asthma trigger for another person. Some people have only one asthma trigger, like exercise or viruses, and others may have a long list of allergens and other triggers.
Allergic triggers include allergens most of us are aware of—pollen, grasses, molds, and dust. Non-allergic triggers include exercise, colds/viruses, chemicals such as perfumes or cleaners, weather like cold air or humidity, smoke and stress. 
It is important to avoid triggers when possible, such as cigarette smoke and animal dander (if you are allergic to it). Some triggers may not be avoidable, and in these situations, it is essential to have an Asthma Action Plan created by your doctor to help manage asthma symptoms with medications.
How is Asthma Treated?
There is no cure for asthma, but it can be treated. Medications are used to treat the underlying inflammation in the airways, as well as to relieve the constriction of muscles surrounding the airways.  Other treatments include medications that deal with the allergic components of asthma, and newer treatments that work on different pathways specific to your asthma—these are called biologics and are most often reserved for severe asthma that is resistant to other treatments.
If asthma is not treated, permanent scarring can develop causing lung damage.  This damage not only makes asthma symptoms worse but also can affect how well you respond to treatment. It is important to take control of your asthma to avoid long-term lung damage.
Who Gets Asthma?
Depending on where you live, between 8 and 10 percent of the population may have asthma . While asthma often develops in childhood, it can develop at any age. If you have close relatives with asthma, eczema or allergies, you may be more likely to get asthma yourself.
Asthma cannot be prevented, but it is very treatable. If you think you have asthma, speak with your doctor. They can do breathing tests to determine if you do have asthma. If you have been diagnosed with asthma, you’re in good company—alongside professional musicians, elite Olympic athletes, and many other people you probably know well! Asthma is not always easy to deal with, but once you can take control of asthma, it does not have to control your life!
Information on this page is for reference and educational purposes only. For more information about asthma, talk to your doctor or primary care provider.
Page last updated: October 4, 2018
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