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Symptoms and Signs of Asthma Definition, Signs, Causes, Types, Treatment, Cure, and Prevention

Doctor's Notes on Asthma

Asthma is a disease that is a result of chronic (ongoing, long-term) inflammation of the breathing passages of the lungs. This makes the airways highly sensitive to various "triggers." When the inflammation is "triggered", the walls of the passages swell, and the openings fill with mucus. Muscles within the breathing passages contract (bronchospasm), causing even further narrowing, which makes it difficult for air to be exhaled from the lungs. This resistance to exhaling leads to the typical symptoms of an asthma attack. Common asthma triggers include exposure to tobacco smoke, pollution, perfumes or cleaning products, exposure to airway irritants at the workplace, inhaling allergens (such as molds, dust, or animal dander), upper respiratory infection, cold or dry weather, stress, physical exertion, gastroesophageal reflux disease (GERD), sulfites, and menstruation.

Symptoms of an asthma attack include wheezing, breathlessness, chest tightness, coughing, and difficulty speaking. The severity of asthma can change over time, and it may improve or worsen.

Medical Author: John P. Cunha, DO, FACOEP
Medically Reviewed on 3/11/2019

Asthma Symptoms

When the breathing passages become irritated or infected, an attack is triggered. The attack may come on suddenly or develop slowly over several days or hours. The main symptoms that signal an attack are as follows:

  • wheezing,
  • breathlessness,
  • chest tightness,
  • coughing, and
  • difficulty speaking.

Symptoms may occur during the day or at night. If they happen at night, they may disturb your sleep.

Wheezing is the most common symptom of an asthma attack.

  • Wheezing is a musical, whistling, or hissing sound with breathing.
  • Wheezes are most often heard during exhalation, but they can occur during breathing in (inhaling).
  • Not all asthmatics wheeze, and not all people who wheeze are asthmatics.

Current guidelines for the care of people with asthma include classifying the severity of asthma symptoms, as follows:

  • Mild intermittent: This includes attacks no more than twice a week and nighttime attacks no more than twice a month. Attacks last no more than a few hours to days. Severity of attacks varies, but there are no symptoms between attacks.
  • Mild persistent: This includes attacks more than twice a week, but not every day, and nighttime symptoms more than twice a month. Attacks are sometimes severe enough to interrupt regular activities.
  • Moderate persistent: This includes daily attacks and nighttime symptoms more than once a week. More severe attacks occur at least twice a week and may last for days. Attacks require daily use of quick-relief (rescue) medication and changes in daily activities.
  • Severe persistent: This includes frequent severe attacks, continual daytime symptoms, and frequent nighttime symptoms. Symptoms require limits on daily activities.

Just because a person has mild or moderate asthma does not mean that he or she cannot have a severe attack. The severity of asthma can change over time, either for better or for worse.

Asthma Causes

The exact cause of asthma is not known.

  • What all people with asthma have in common is chronic airway inflammation and excessive airway sensitivity to various triggers.
  • Research has focused on why some people develop asthma while others do not.
  • Some people are born with the tendency to have asthma, while others are not. Scientists are trying to find the genes that cause this tendency.
  • The environment you live in and the way you live partly determine whether you have asthma attacks.

An asthma attack is a reaction to a trigger. It is similar in many ways to an allergic reaction.

  • An allergic reaction is a response by the body's immune system to an "invader."
  • When the cells of the immune system sense an invader, they set off a series of reactions that help fight off the invader.
  • It is this series of reactions that results in inflammation of the lining of the air passages. This can result in a modification of the cell types lining these airways. More glandular-type cells develop, which can cause the production of mucus. This mucus, along with irritation to muscle receptors in the airways, can cause bronchospasm. These responses cause the symptoms of an asthma attack.
  • In asthma, the "invaders" are the triggers listed below. Triggers vary among individuals.
  • Because asthma is a type of allergic reaction, it is sometimes called reactive airway disease.

Each person with asthma has his or her own unique set of triggers. Most triggers cause attacks in some people with asthma and not in others. Common triggers of asthma attacks include

Risk factors for developing asthma include

  • hay fever (allergic rhinitis) and other allergies (This is the single biggest risk factor.),
  • eczema (another type of allergy affecting the skin), and
  • genetic predisposition (a parent, brother, or sister also has asthma).

Asthma Symptoms, Causes, and Medications Slideshow

Asthma Symptoms, Causes, and Medications  Slideshow

Asthma is a chronic lung disorder that can make breathing difficult by narrowing and inflaming the airways (bronchial tubes).

“Asthma” is an ancient Greek word meaning “short breath, panting.” One of the telltale signs of asthma attacks is the wheezing and breathing difficulty that they cause.

Asthma attacks can be a frightening experience, and affect breathing by causing

  • inflammation, swelling, and narrowing of the airways,
  • recurring wheezing,
  • chest tightness,
  • coughing, and
  • shortness of breath.

Chronically inflamed bronchial tubes become very sensitive to inhaled allergens or irritants such as

  • pollen,
  • pollution,
  • tobacco smoke, or
  • triggers such as exercise.

Prevalence of Asthma

About 25 million people in the U.S. have asthma; 7 million of those are children. Asthma reports are on the rise. The condition affects men and women equally. Asthma causes over 14 million visits to doctors each year and nearly 2 million visits to emergency departments.

Asthma Can Be Deadly

Asthma can kill. The rate of asthma deaths spiked from 2,600 in 1979 up to 4,600 in 1988. The reasons for this spike are unknown, but may be related to

  • inadequate medical care,
  • an increased severity of asthma, and/or
  • an increase in the number of people with asthma.

African Americans are about three times as likely to die from asthma as white Americans. Most people who die from asthma are over age 50, but children sometimes die of the condition, too.


Kasper, D.L., et al., eds. Harrison's Principles of Internal Medicine, 19th Ed. United States: McGraw-Hill Education, 2015.