Bronchial asthma


Take a deep breath

More than 17 million Americans have been diagnosed with asthma, a chronic episodic respiratory disease marked by asthma attacks. During an attack, the respiratory system overreacts to normally harmless substances or circumstances and small airways in the lungs constrict. The result is wheezing, coughing, difficulty breathing, a sense of tightness in the chest, and sometimes a cough that produces a thick, clear mucus. New anti-inflammatory drugs have helped make asthma much more manageable than it once was. Nonetheless, asthma remains a potentially fatal illness, killing some 5,000 Americans each year.

Detailed Description

Asthma is a condition in which the airways of the lungs narrow in response to environmental triggers (pollens, dust, animal dander, smoke), cold air, exercise, respiratory infection, or emotional distress. Some people suffer asthma attacks as an allergic response to various airborne environmental triggers. The body mistakes the allergen for an enemy invader and works to counteract it. There are many allergens that can trigger an asthma response, and everyone susceptible responds to different ones — and to different degrees. But whatever the trigger, narrowing of the airways is the result.

In an asthma attack, the air passages of the lungs, known as bronchi, overreact to substances that are ordinarily harmless. Cells in the airways known as mast cells release histamines and leukotrienes, which induce inflammation. These substances prompt the smooth muscles of the airways to go into spasm and constrict. They also cause white blood cells to migrate into the affected regions of the airways. Soon, the bronchi become inflamed and release mucus, which further blocks the passage of air. Narrowing of the air passages is known as bronchoconstriction. When the airways are reduced in diameter, more effort is required to move air into and out of the lungs, and breathing becomes difficult.

Characteristics of Asthma

Asthma is not a contagious disease, nor does it have psychological roots. It is a condition that typically doesn't create daily symptoms. Rather, asthma sufferers endure recurrent episodes of breathing difficulties — asthma attacks. They can be mild or severe, last only minutes or go on for hours or even days. They can end spontaneously, but most require treatment.

Some people with asthma are free of symptoms most of the time, with only an occasional episode of shortness of breath that is both brief and mild. Others cough and wheeze much of the time or have severe attacks after viral infections, exercise, or exposure to allergens. Sometimes crying or hearty laughing can bring on symptoms.

An asthma attack can come on suddenly with wheezing, coughing, and shortness of breath, or may come on gradually and worsen slowly. An asthma attack usually requires immediate treatment and recovery is complete even when the attack was severe.

How Common Is Asthma?

In spite of many advances in treatment and management, the number of emergency-room visits, hospitalizations, deaths, urgent-care visits, and lost work or school days due to asthma continues to rise. The number of people who suffer from asthma is also rising. Asthma cases in America have more than doubled from 6.8 million in 1980 to 15 million in 1996. Currently there are more than 17 million Americans — approximately one in 20 — who have asthma.

The number of deaths due to asthma is also rising. Deaths have escalated from 2,600 per year in 1979 to 5,000 in 1996. These figures are particularly discouraging because asthma is largely manageable. In addition, the affliction strikes African-Americans particularly hard. According to the American Lung Association, African-Americans account for 12% of all people with the condition, but 21% of asthma deaths.

Asthma occurs in all age groups, but 50% of all cases occur in children under age 10 and most cases occur prior to age 25. For children under age 10, asthma is more common in boys than girls. At puberty, the disorder is equally spread between the sexes; in adults, more females contract the ailment than males. Some 40% of children with asthma "outgrow" the disease when they reach adulthood.

The condition increasingly seems to be manifesting itself more severely, requiring more sufferers to be hospitalized. Some experts believe this trend is based on a rise in airborne environmental pollutants. Asthma is now the most common chronic ailment among children, and there is some evidence to suggest that asthma may run in families. The search for an asthma gene is currently underway.

What You Can Expect

  • Mild or moderate asthma. In a mild or moderate attack (the more common form of attack) you may start to feel tightness in your chest and start coughing or spitting up mucus. You may also feel restless or unable to sleep if you are trying, and make a wheezing or whistling sound when you breathe. Wheezing occurs as you try to breathe air in and out through air tubes that are narrowed and constricted.
  • Severe attacks. In a severe attack, you may become utterly breathless, and as you become less and less able to breathe you may have trouble talking. Your neck muscles may become tight as you strain with the difficulty of breathing. And because the amount of oxygen you are taking in is decreasing, you may find that your lips and fingernails develop a grayish or bluish hue (cyanosis). The skin around the ribs of your chest might appear sucked in.
  • Second-wave attacks. In some cases, your asthma attack may seem to ease up. But changes may take place in your air tubes that cause another attack — what is called a "second wave." This second attack can be more severe and more dangerous than the first.

    In the second wave, the air tubes continue to swell even when asthma symptoms seem to have disappeared. Difficulty breathing may last days or even weeks after the first attack. In the meantime, your lungs become more sensitive and the possibility of more attacks rises.

In all cases of asthma, it is necessary to see a doctor to determine how severe your condition is and to set you up with a medication regimen that will relax tightened muscles and reduce the constriction and inflammation in your airways.

Conventional Treatment

Goals of Treatment

The goal of treatment for those with asthma is to lessen the frequency and severity of asthma attacks or episodes. Your doctor will prescribe medicine that can help prevent asthma attacks, quickly relieve symptoms if an attack occurs, and help you achieve maximum lung function with minimum drug use.

Treatment Overview

Treatment for asthma revolves primarily around drug therapies. Many of the same drugs used to prevent an attack are used in higher doses to relieve symptoms during an attack. The most common and effective treatment is an inhaler filled with a beta-adrenergic receptor agonist — a medication designed to inhibit production of the chemicals produced by your body that cause the airways to narrow.

Either a hand-held inhaler or a nebulizer containing a beta-adrenergic receptor agonist (a bronchodilator) is used. Sometimes an injection of epinephrine or terbutaline under the skin and an intravenous infusion of aminophylline are used. However, these latter treatments are considered less effective than bronchodilators.

Because people with severe asthma commonly have low blood-oxygen levels, it may be appropriate to administer oxygen during an attack. Corticosteroid injections are given if those having a severe attack show no improvement.

Drug Therapy

Drugs most commonly prescribed

Asthma can usually be treated effectively with bronchodilators that widen airways, anti-inflammatory agents and medications that block the smooth-muscle receptors that prompt airway constriction. It can also be treated with a leukotriene inhibitor. Leukotriene is the chemical substance responsible for the inflammation that occurs in the airways of the lungs. Leukotriene inhibitors block the action of leukotrienes before an asthma attack occurs.

Different asthma medications are prescribed depending on the severity and frequency of asthma attacks.


On-Label Efficacy


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On-Label Efficacy


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On-Label Efficacy

Activity & Diet Recommendations

Improving your overall health by developing a healthier diet may make you less susceptible to stress and respiratory infection — two conditions that can lead to asthma. In addition, some specific foods — egg yolks, chocolate, fish, shellfish, and nuts — seem to be particular culprits in triggering asthma attacks in susceptible people. If you suspect certain foods, keep a list and avoid them.

Also, try to drink plenty of fluids (six to eight glasses of water daily is the recommendation) to help keep respiratory mucus thin.

Possible Complications

Possible complications of asthma include:

  • Respiratory failure
  • Pneumothorax
  • Lung infection
  • Chronic obstructive pulmonary disease (COPD)
  • Atelectasis (lack of gas in lungs)
  • Death

Quality of Life

Having poorly controlled asthma can be an emotional roller-coaster; asthma attacks, or anticipating them, can produce tremendous anxiety. By the same token, anxiety can actually spark an attack. It can also be a challenge to stick to both the medicinal regimen required to manage the condition and the lifestyle adjustments necessary to keep attacks in check. Nevertheless, adhering to your prescribed regimen is the best way to stay free of asthma symptoms.

Considerations for Women

Be sure to let your doctor know if you are taking oral contraceptives. The chemistry of oral contraceptives is such that they may raise the levels of asthma medications (such as theophylline) in your blood and cause nausea, vomiting, restlessness, and irritability.


  • If you are pregnant and have asthma, you should take particular care to avoid stress and develop techniques to reduce it.
  • With your doctor's help, avoid particular asthma medications that could be harmful if taken during pregnancy. Inhaled steroids are okay, and low-dose oral steroids do not pose a threat of birth defects in a developing fetus.
  • About 50% of pregnant asthma sufferers notice no change in their symptoms during pregnancy, while 25% notice an improvement. Another 25% seem to have worse symptoms when pregnant.

Nursing mothers

Avoid theophylline if you are breastfeeding. It is found in the breast milk of those who take it in the prescribed dose. Talk to your healthcare provider to find an alternative way to treat your asthma.

Considerations for Older People

In older people, asthma may occur in conjunction with other forms of chronic obstructive pulmonary disease (COPD), such as chronic bronchitis and emphysema. Your doctor will help you control your asthma and cough, reduce the formation of mucus in your bronchial tubes, and prevent lung infections.

Considerations for Children and Adolescents

Asthma is primarily a disease of childhood, with almost five million cases occurring in children under age 14. In addition, 50% of all new cases occur in children under age 10, making it especially difficult to manage. Some guidelines for helping your child live comfortably with asthma:

  • If you smoke, quit. At the very least, do not smoke in your house or in your child's presence or allow anyone else to do so, since it may aggravate the symptoms.
  • Be vigilant about cleaning up the allergens and irritants in your homes (consider a special vacuum cleaner that traps and retains microscopic particles).
  • Be aware of the foods that may prompt an attack in your child and eliminate them.
  • Overprotection can be harmful. Make every attempt to keep your child active with friends and in school.
  • Keep medications with your child. Ask your doctor about having emergency drugs available.
  • Have your child sit upright during an attack. If the attack follows exercise, your child should sit and sip warm water.

ALERT: If your child does not respond to treatment for an asthma attack, call your doctor immediately. This is an emergency!

Alternative care


  • Vitamin C: may be helpful. Researchers at the New Jersey Medical School in Newark reviewed dozens of studies of asthma and vitamin C and found this conclusion: As the blood level of vitamin C decreases, the risk of respiratory problems increases. As vitamin C intake rises, risk of asthma attacks seems to decline.
  • Magnesium: may also prove helpful. British researchers performed lung function tests on 2,633 adults and also rated their magnesium intake through use of a diet survey. Those lowest in magnesium were most likely to have asthma. When members of the low-magnesium group took supplements or ate foods rich in the mineral — including beans, whole grains, and dairy products — their lung function improved.


An ancient Hindu discipline, yoga provides gentle stretching and strengthening exercises combined with controlled breathing, focused concentration, and meditation.

In an Indian study of 106 asthmatic adults, half received standard medical care and half took two weeks of yoga training, after which they were encouraged to practice it on their own. Four years later, those who did yoga regularly had fewer asthma attacks and used less asthma medication.


Biofeedback is a relaxation technique that trains you to control automatic body functions, like heartbeat, that you might not think could be voluntarily controlled. At San Francisco State University, researchers used biofeedback to teach 21 asthmatics to breathe slowly and deeply. After 15 months, 80% of them reported fewer attacks and less use of asthma medication.


An ancient Chinese practice, acupuncture consists of inserting very fine needles into the skin along a series of energy channels or paths known as meridians. It stimulates particular areas or systems of the body to promote healing and wellness. Acupuncture can help relieve asthma, as shown by these two studies:

  • Nineteen asthmatic children received either real or pretend acupuncture. Afterward, the real-acupuncture group experienced significantly fewer asthma symptoms.
  • Seventeen asthmatics received 10 treatments of either real or pretend acupuncture over five weeks. The true-acupuncture group "improved significantly throughout the study," and needed less asthma medication.
Bronchial asthma

Last updated 25 May 2012


  • Bronchial asthma
  • Reversible hyper-reactive lung disease
  • Reversible airway disease
  • Reversible obstructive airway disease




Established Causes

The exact trigger that prompts an asthma attack varies with the type of asthma you have.

  • Extrinsic (allergic) asthma. Extrinsic asthma is due to a true allergy, where an offending substance known as an antigen causes an allergic response. When exposed to an antigen, the body releases antibodies — immunoglobulin molecules that react with the offending antigen. Common allergens are household dust mites, airborne pollens, and animal dander.
  • Intrinsic (idiosyncratic) asthma. This type of asthma has no identifiable cause. The onset of this type of asthma usually occurs in people between ages 35 and 45. Of those with intrinsic asthma, 10% to 15% are sensitive to aspirin.
  • Occupational asthma. An allergic reaction to substances you breathe at work. Hair bleaches and dyes, for example, may trigger asthma in beauticians, while flour may cause attacks in bakers or food workers.
  • Exercise-induced asthma. Exercise can trigger an asthmatic response in some people. This type of asthma may either occur on its own or in conjunction with other types of asthma.

In addition, asthma may be triggered by the following causes:

  • Cold air (or rapid temperature changes)
  • Cigarette smoke
  • Cooking odors
  • Perfumes and fragrances
  • Emotional stress and anxiety
  • Sulfites
  • Food additives such as monosodium glutamate (MSG)
  • Virus, fungus, or bacteria
  • Air pollution
  • Gastroesophageal reflux: Asthma may be caused by chronic irritation of the lungs from gastric acid that has splashed up into the esophagus and has entered the airway. Onset of asthma, especially in adults, may warrant evaluation for reflux.

Theoretical Causes

The presence of an asthma gene is currently being investigated.

Risk Factors

Risk factors for asthma include:

  • Family history of asthma or allergies
  • Exposure to air pollutants, molds, household dust mites, animal dander, feather pillows
  • Allergic conditions such as eczema or hay fever
  • Viral lower-respiratory infection during infancy (controversial)
  • Smoking or exposure to secondhand tobacco smoke.
  • Use of aspirin, nonsteroidal anti-inflammatory drugs (NSAIDs), or exposure to tartrazine dyes
  • Upper-respiratory infection during infancy

Symptoms & Diagnosis

Typical asthma symptoms include:

  • Wheezing (a rasping or whistling sound, particularly as you breathe out)
  • Coughing or spitting up mucus
  • Difficulty breathing or struggling for air
  • Rapid breathing
  • Shortness of breath that may create a feeling of anxiety
  • Tightness in the chest
  • Coughing, especially at night or while exercising, with little sputum production
  • Itching on the chest or neck may be an early indicator, especially in children
  • Rapid heartbeat
  • Confusion, lethargy, and blue skin color (cyanosis) may be present during severe asthma attacks, indicating insufficient oxygen inhalation
  • A person experiencing an asthma attack may instinctively sit upright and lean forward to facilitate easier breathing — sweating is a common reaction to this effort
  • In a severe attack, a person may be able to speak only a few words without stopping for a breath first

Conditions That May Be Mistaken for Asthma

There are a number of conditions that can resemble asthma and complicate a correct diagnosis. For patients exhibiting atypical asthma symptoms or for those who fail to respond to therapy, it is wise to consider these conditions. Disorders that resemble asthma tend to fall into one of four categories:

  • Upper airway disorders
    • Vocal-cord paralysis
    • Vocal-cord dysfunction syndrome
    • Foreign-body aspiration
    • Laryngotracheal masses
    • Tracheal narrowing
    • Tracheomalacia
  • Lower airway disorders
    • Acute and chronic bronchitis
    • Emphysema
    • Bronchiectasis
    • Allergic bronchopulmonary mycosis
    • Cystic fibrosis
    • Eosinophilic pneumonia
    • Lung cancer
    • Carcinoid syndrome
  • Systemic vasculitides
    • Churg-Strauss syndrome
    • Polyateritis nodosa
  • Psychiatric disorders
    • Conversion disorders

The following conditions should also be ruled out:

  • Epiglottitis
  • Mitral valve prolapse
  • Habit coughing
  • Congestive heart failure

How Asthma Is Diagnosed

A doctor suspects asthma based largely on the patient's report of asthma symptoms. It can then be confirmed through the use of a spirometer (a recording device that measures the volume of air inhaled or exhaled and the length of time each breath takes). The test can be conducted several times over a number of hours or days during an attack. A peak expiratory flow test (which measures the speed at which you can exhale) may also be conducted, or an inhalation bronchial challenge, which checks for allergic asthma.

Laboratory Work

Your doctor may perform laboratory tests to determine if you have asthma. A sweat test may be conducted in children to rule out cystic fibrosis. He may also check for arterial blood gases during an acute and severe episode, and make sure that your complete blood count is normal.

Specific Tests

Your doctor may perform the following tests to help in the diagnosis:

  • Pulmonary function tests: spirometry, peak expiratory flow and peak flow meter
  • Skin testing to identify what you are allergic to and what triggers your asthma episodes
  • Exercise tolerance testing for exercise-induced asthma


Chest X-ray to determine if there are lung complications such as pneumonia

Self care & Prevention

Asthma symptoms usually get started, or are triggered by, a substance that bothers the lungs. Those substances include viruses (such as a cold or flu) and allergens, gases and particles in the air. Given this range, you may find it hard to figure out what starts your asthma attacks. You may even think your attacks "just happen." But this is generally not true; something usually triggers an attack.

Once you find out what your triggers are, you can avoid them and thus aid in preventing attacks. This will give you control. You are likely not to have them as often and, if you do have an attack, there's a good chance it will be less severe. You will have to be conscientious about taking your medicine as prescribed and act to counteract asthma symptoms as soon as they occur.

Prevention also includes avoiding later complications such as emphysema and heart disease.

Preventing Asthma Attacks

Controlling and preventing any lung disease requires attention. Here's what you can do:

  • Don't smoke. Quitting smoking is the best protection you can give your lungs and reduces your risk of lung disease. Your local American Lung Association can help.
  • Be honest. Understand that chronic cough, shortness of breath and other lung symptoms are not normal.
  • Take action. Bring any lung disease symptom to a doctor's attention early. Then follow the doctor's advice.
  • Avoid lung hazards. Secondhand cigarette smoke, air pollution, and hazards at work can cause lung disease.
  • Avoid known allergens, aspirin, and food additives.
  • Drink plenty of nonalcoholic fluids (six to eight glasses daily) to keep bronchial mucus thin.
  • Think about prevention. Lung disease like influenza and pneumococcal pneumonia can be prevented with vaccination.
  • Avoid sedatives.
  • Try a regimen of hyposensitization (where small doses of the allergen are injected daily to increase tolerance).

Self-Care Measures

  • Take your asthma medicines as prescribed, even if you feel well.
  • In the case of a severe asthma attack, take your asthma medicine and get emergency medical help right away if symptoms don't subside.
  • Get regular moderate exercise. Don't let asthma keep you from being active, since exercise helps normalize lung function.
  • Pay attention to air-quality reports in the news media. On high-pollution days, try to limit your time outdoors. Exercise indoors.
  • Monitor your peak flow. Peak flow is the amount of air you exhale in one breath. Peak flow drops shortly before asthma attacks.
  • Regular home monitoring establishes your baseline and gives you early warning of developing asthma. If peak flow falls below 70% of baseline levels, contact your physician. If levels are lower than 50% of baseline, air flow is severely compromised and you should seek emergency medical care.