What Is Asthma?

Asthma is a long-term disease of the lungs. It causes your airways to get inflamed and narrow, and it makes it hard to breathe. Severe asthma can cause trouble talking or being active. You might hear your doctor call it a chronic respiratory disease. Some people refer to asthma as "bronchial asthma."

Asthma is a serious disease that affects about 25 million Americans and causes nearly 2 million emergency room visits every year. With treatment, you can live well. Without it, you might have to go to the ER often or stay at the hospital, which can affect your daily life.

Symptoms of Asthma

There are three major signs of asthma:

  • Airway blockage. When you breathe as usual, the bands of muscle around your airways are relaxed, and air moves freely. But when you have asthma, the muscles tighten. It’s harder for air to pass through.
  • Inflammation . Asthma causes red, swollen bronchial tubes in your lungs. This inflammation can damage your lungs. Treating this is key to managing asthma in the long run.
  • Airway irritability. People with asthma have sensitive airways that tend to overreact and narrow when they come into contact with even slight triggers.

These problems may cause symptoms such as:

When to see your doctor

Get medical help right away if you have serious symptoms including:

  • Fast breathing
  • Pale or blue face, lips, or fingernails
  • The skin around your ribs pulls inward when you breathe in
  • Trouble breathing, walking, or talking
  • Symptoms that don’t get better after you take medication

What Is an Asthma Attack?

An asthma attack is when your symptoms suddenly get worse. Your airways tighten, swell, or fill with mucus.

Not every person with asthma has the same symptoms with an asthma attack. You may have different ones at different times. They may be less obvious, like having less energy. They may also range from mild to severe between one attack and the next.


How Is Asthma Classified?

Doctors rank how bad asthma is by its symptoms:

  1. Mild intermittent asthma. Mild symptoms less than twice a week. Nighttime symptoms less than twice a month. Few asthma attacks.
  2. Mild persistent asthma. Symptoms three to six times a week. Nighttime symptoms three to four times a month. Asthma attacks might affect activities.
  3. Moderate persistent asthma. Symptoms three to six times a week. Nighttime symptoms three to four times a month. Asthma attacks might affect activities.
  4. Severe persistent asthma. Ongoing symptoms both day and night. You have to limit your activities.

Your asthma may be getting worse if:

  • You have symptoms more often and they interfere more with your daily life.
  • You have a hard time breathing. You can measure this with a device called a peak flow meter.
  • You need to use a quick-relief inhaler more often.

Types of Asthma

There are several:

  • Adult-onset asthma. Asthma can start at any age, but it's more common in people younger than 40.
  • Status asthmaticus . These long-lasting asthma attacks don’t go away when you use bronchodilators. They’re a medical emergency that needs treatment right away.
  • Asthma in children. Symptoms can vary from episode to episode in the same child. Watch for problems like:
    • Coughing often, especially during play, at night, or while laughing. This may be the only symptom.
    • Less energy or pausing to catch their breath while they play
    • Fast or shallow breathing
    • Saying their chest hurts or feels tight
    • A whistling sound when they breathe in or out
    • Seesaw motions in their chest because of trouble breathing
    • Shortness of breath
    • Tight neck and chest muscles
    • Weakness or fatigue
  • Exercise-induced bronchoconstriction. You might hear this called exercise-induced asthma. It happens during physical activity, when you breathe in air that’s drier than what’s in your body, and your airways narrow. It can affect people who don’t have asthma, too. You’ll notice symptoms within a few minutes after you start to exercise, and they might last 10 to 15 minutes after you stop.
  • Allergic asthma. Things that trigger allergies, like dust, pollen and pet dander, can also cause asthma attacks.
  • Nonallergic asthma. This type flares in extreme weather. It could be the heat of summer or the cold of winter. It could also show up when you’re stressed or have a cold.
  • Occupational asthma. This usually affects people who work around chemical fumes, dust, or other irritating things in the air.
  • Eosinophilic asthma. This severe form is marked by high levels of white blood cells called eosinophils. It usually affects adults between 35 and 50 years old.
  • Nocturnal asthma. Your asthma symptoms get worse at night.
  • Aspirin-induced asthma. You have asthma symptoms when you take aspirin, along with a runny nose, sneezing, sinus pressure, and a cough.
  • Cough-variant asthma. Unlike with other types, the only symptom of this kind of asthma is a long-term cough.


Asthma Causes and Triggers

When you have asthma, your airways react to things in the world around you. Doctors call these asthma triggers. They might cause symptoms or make them worse. Common asthma triggers include:

  • Infections like sinusitis, colds, and the flu
  • Allergens such as pollens, mold, pet dander, and dust mites
  • Irritants like strong odors from perfumes or cleaning solutions
  • Air pollution
  • Tobacco smoke
  • Exercise
  • Cold air or changes in the weather, such as temperature or humidity
  • Gastroesophageal reflux disease (GERD)
  • Strong emotions such as anxiety, laughter, sadness, or stress
  • Medications such as aspirin
  • Food preservatives called sulfites, found in things like shrimp, pickles, beer and wine, dried fruits, and bottled lemon and lime juices

Asthma Risk Factors

Things that might make you more likely to have asthma include:

  • Things in the world around you before you’re born or while you’re growing up
  • Whether your parents have asthma, especially your mother
  • Your genes
  • Your race. Asthma is more common in people of African American or Puerto Rican descent.
  • Your sex. Boys are more likely to have asthma than girls. In teens and adults, it’s more common in females.
  • Your job
  • Other conditions like lung infections, allergies, or obesity

Asthma Diagnosis

If you think you have asthma, see your doctor. They’ll refer you to an asthma specialist, also known as a pulmonologist.

The doctor will start with a physical exam and ask about your symptoms and medical history.

You’ll have tests to see how well your lungs work, including:

  • Spirometry. This simple breathing test measures how much air you blow out and how fast.
  • Peak flow. These measure how well your lungs push out air. They’re less exact than spirometry, but they can be a good way to test your lungs at home, even before you feel any symptoms. A peak flow meter can help you figure out what makes your asthma worse, whether your treatment is working, and when you need emergency care.
  • Methacholine challenge. Adults are more likely to have this test than children. You might get it if your symptoms and spirometry test don’t clearly show asthma. During this test, you inhale a chemical called methacholine before and after spirometry to see if it makes your airways narrow. If your results fall at least 20%, you have asthma. You doctor will give you medicine at the end of the test to reverse the effects of the methacholine.
  • Exhaled nitric oxide test. You breathe into a tube connected to a machine that measures the amount of nitric oxide in your breath. Your body makes this gas normally, but levels could be high if your airways are inflamed.

Other tests you might get include:

  • Chest X-ray. It isn’t an asthma test, but your doctor can use it to make sure nothing else is causing your symptoms. An X-ray is an image of the inside of your body, made with low doses of radiation.
  • CT. This test takes a series of X-rays and puts them together to make a view of your insides. A scan of your lungs and sinuses can identify physical problems or diseases (like an infection) that may cause breathing problems or make them worse.
  • Allergy tests. These can be blood or skin tests. They tell if you’re allergic to pets, dust, mold, and pollen. Once you know your allergy triggers, you can get treatment to prevent them -- and asthma attacks.
  • Sputum eosinophils. This test looks for high levels of white blood cells (eosinophils) in the mix of saliva and mucus (sputum) that comes out when you cough.


Asthma Treatment

Many asthma treatments can ease your symptoms. Your doctor will work with you to make an asthma action plan that will outline your treatment and medications. They might include:

  • Inhaled corticosteroids. These medications treat asthma in the long term. That means you’ll take them every day to keep your asthma under control. They prevent and ease swelling inside your airways, and they may help your body make less mucus. You’ll use a device called an inhaler to get the medicine into your lungs. Common inhaled corticosteroids include:
  • Leukotriene modifiers. Another long-term asthma treatment, these medications block leukotrienes, things in your body that trigger an asthma attack. You take them as a pill once a day. Common leukotriene modifiers include:
  • Long-acting beta-agonists. These medications relax the muscle bands that surround your airways. You might hear them called bronchodilators. You’ll take these medications with an inhaler, even when you have no symptoms. They include:
    • Formoterol (Foradil)
    • Salmeterol (Serevent)
  • Combination inhaler. This device gives you an inhaled corticosteroid and a long-acting beta-agonist together to ease your asthma. Common ones include:
  • Theophylline. It opens your airways and eases tightness in your chest. You take this long-term medication by mouth, either by itself or with an inhaled corticosteroid.
  • Short-acting beta-agonists. These are known as rescue medicines or rescue inhalers. They loosen the bands of muscle around your airways and ease symptoms. Examples include:
  • Anticholinergics. These bronchodilators prevent the muscle bands around your airways from tightening. Common ones include:

You can get ipratropium in an inhaler or as a solution for a nebulizer, a device that turns liquid medicine into a mist that you breathe in through a mouthpiece. Tiotropium bromide comes in a dry inhaler, which lets you breathe in the medicine as a dry powder.

  • Oral and intravenous corticosteroids. You’ll take these along with a rescue inhaler during an asthma attack. They ease swelling and inflammation in your airways. You’ll take oral steroids for a short time, between 5 days and 2 weeks. Common oral steroids include:


You’re more likely to get steroids injected directly into a vein if you’re in the hospital for a bad asthma attack. This will get the medication into your system more quickly.

  • Biologics. If you have severe asthma that doesn’t respond to control medications, you might try a biologic:
    • Omalizumab (Xolair) treats asthma caused by allergens. You get it as an injection every 2 to 4 weeks.
    • Other biologics stop your immune cells from making things that cause inflammation. These drugs include:

Home remedies

Medication will probably be key to getting your asthma under control, but you can do some things at home to help.

  • Avoid asthma triggers.
  • Exercise regularly.
  • Keep a healthy weight.
  • Take care of conditions that can trigger symptoms, such as GERD.
  • Do breathing exercises to ease symptoms so you need less medication.
  • Some people use complementary treatments such as yoga, acupuncture, biofeedback, or supplements like vitamin C and ding chuan tang. Talk to your doctor before trying any of these.

Asthma Complications

When it’s not under control, asthma can cause problems with your daily life, such as:

Asthma can also lead to serious medical conditions including:

  • Pneumonia and other complications from common infections like the flu
  • Early delivery or the loss of a pregnancy
  • Permanently narrowed bronchial tubes in your lungs
  • Lung collapse
  • Respiratory failure

Asthma Attack Prevention

Your action plan will include different ways to keep your asthma under control and prevent attacks. These might include:

  • Know your triggers, and stay away from them.
  • Follow your doctor’s instructions on taking your asthma medications. Let them know if you notice that you’re using a quick-relief inhaler more often.
  • Keep track of your condition and learn the signs that it might be getting worse. A peak flow meter can help.
  • Know what to do if you think your asthma is getting worse.
  • Talk to your doctor about vaccines to lower your chances of certain conditions. You might get vaccinations for flu, pneumonia, shingles, or whooping cough (pertussis).
WebMD Medical Reference Reviewed by Gabriela Pichardo on May 15, 2019



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