What’s asthma?

Asthma is a disease that affects your lungs’ airways. It is a chronic (ongoing) condition. A chronic condition doesn’t go away and needs ongoing medical management.

Asthma affects more than 24 million people in the United States. This total includes roughly 5.5 million children. Asthma can be life-threatening if you don’t get treatment.

What’s an asthma attack?

When you breathe normally, muscles around your airways are relaxed, letting air move easily. During an asthma attack, three things can happen:

  • Bronchospasm: The muscles around the airways constrict (tighten). When they tighten, it makes the airways narrow. Air cannot flow freely through constricted airways.
  • Inflammation: The airway linings become swollen. Swollen airways don’t let as much air in or out of the lungs.
  • Mucus production: During the attack, your body creates more mucus. This thick mucus clogs airways.

What types of asthma are there?

Healthcare providers identify asthma as intermittent (comes and goes) or persistent (lasting). Persistent asthma can be mild, moderate or severe. Healthcare providers base asthma severity on how often you have attacks. They also consider how well you can do things during an attack.

Asthma can be:

  • Allergic: Some people’s allergies can cause an asthma attack. Molds, pollens and other allergens can cause an attack.
  • Non-allergic: Outside factors can cause asthma to flare up. Exercise, stress, illness and weather may cause a flare.

Who can get asthma?

Anyone can develop asthma at any age. People with allergies or people exposed to tobacco smoke and secondhand smoke are more likely to develop asthma.

Statistics show women tend to have asthma more than men, and asthma affects Black Americans more frequently than other races.

When a child develops asthma, healthcare providers call it childhood asthma. If it develops later in life, it’s adult-onset asthma.

Children do not outgrow asthma. They may have fewer symptoms as they get older, but they could still have an asthma attack. Your child’s healthcare provider can help you understand the risks.

Symptoms and Causes

What causes asthma?

Healthcare providers don’t know why some people have asthma while others don’t. But certain factors present a higher risk:

  • Allergies: Having allergies can raise your risk of developing asthma.
  • Environmental factors: Infants can develop asthma after breathing in things that irritate the airways. These substances include allergens, secondhand smoke and some viral infections. They can harm infants and young children whose immune systems haven’t finished developing.
  • Genetics: People with a family history of asthma have a higher risk of developing the disease.
  • Respiratory infections: Certain respiratory infections, such as respiratory syncytial virus (RSV), can damage young children’s developing lungs.

What are common asthma attack triggers?

An asthma attack happens when someone comes in contact with substances that irritate them. Healthcare providers call these substances “triggers.” Knowing what triggers your asthma makes it easier to avoid asthma attacks.

For some people, a trigger can bring on an attack right away. Sometimes, an attack may start hours or days later.

Triggers can be different for each person. But some common triggers include:

  • Air pollution: Many things outside can cause an asthma attack. Air pollution includes factory emissions, car exhaust, wildfire smoke and more.
  • Dust mites: You can’t see these bugs, but they are in many homes. If you have a dust mite allergy, they can cause an asthma attack.
  • Exercise: For some people, exercising can cause an attack.
  • Mold: Damp places can spawn mold. It can cause problems for people with asthma. You don’t even have to be allergic to mold to have an attack.
  • Pests: Cockroaches, mice and other household pests can cause asthma attacks.
  • Pets: Your pets can cause asthma attacks. If you’re allergic to pet dander (dried skin flakes), breathing in the dander can irritate your airways.
  • Tobacco smoke: If you or someone in your home smokes, you have a higher risk of developing asthma. The best solution is to quit smoking.
  • Strong chemicals or smells.
  • Certain occupational exposures.

What are asthma symptoms?

People with asthma usually have obvious symptoms. These symptoms resemble many respiratory infections:

With asthma, you may not have all of these symptoms. You may have different signs at different times. And symptoms can change between asthma attacks.

Diagnosis and Tests

How do healthcare providers diagnose asthma?

Your healthcare provider will review your medical history, including information about your parents and siblings. Your provider will also ask you about your symptoms. Your provider will need to know any history of allergies, eczema (a bumpy rash caused by allergies) and other lung diseases.

Your healthcare provider may order a chest X-ray, blood test or skin test. Your provider may order spirometry. This test measures airflow through your lungs.

Management and Treatment

What asthma treatment options are there?

You have options to help manage your asthma. Your healthcare provider may prescribe medications to control symptoms. These include:

  • Anti-inflammatory medicines: These medicines reduce swelling and mucus production in your airways. They make it easier for air to enter and exit your lungs. Your healthcare provider may prescribe them to take every day to control or prevent your symptoms.
  • Bronchodilators: These medicines relax the muscles around your airways. The relaxed muscles let the airways move air. They also let mucus move more easily through the airways. These medicines relieve your symptoms when they happen.
  • Biologic therapies for asthma when symptoms persist despite being on proper inhaler therapy.

You can take asthma medicines in several different ways. You may breathe in the medicines using a metered-dose inhaler, nebulizer or other inhaler. Your healthcare provider may prescribe oral medications that you swallow.

What is asthma control?

The goal of asthma treatment is to control symptoms. Asthma control means you:

  • Can do the things you want to do at work and home.
  • Have no (or minimal) asthma symptoms.
  • Rarely need to use your reliever medicine (inhaler).
  • Sleep without asthma interrupting your rest.

How do you monitor asthma symptoms?

Monitoring your asthma symptoms is an essential piece of managing the disease. Your healthcare provider may have you use a peak flow (PF) meter. This device measures how fast you can blow air out of your lungs. It can help your provider make adjustments to your medication. It also tells you if your symptoms are getting worse.


How can I prevent an asthma attack?

If your healthcare provider says you have asthma, you will need to know what triggers an attack. If you know the triggers, you can try to avoid them to avoid an attack. You cannot prevent getting asthma, though.

Outlook / Prognosis

What’s the outlook for someone with asthma?

A person with asthma can live a very productive life, including participating in sports and other activities. Your healthcare provider can help you manage symptoms, learn your triggers and prevent or manage attacks.

Living With

What is an asthma action plan?

Your healthcare provider will work with you to develop an asthma action plan. This plan tells you how and when to use your medicines. It also tells you what to do if your asthma gets worse and when to seek emergency care. Understand the plan and ask your healthcare provider about anything you don’t understand.

What should I do if I have a severe asthma attack?

A severe asthma attack needs immediate medical care. The first step is your rescue inhaler. A rescue inhaler uses fast-acting medicines to open up your airways. It’s different than your normal maintenance inhaler, which you use every day. You should only use the rescue inhaler in an emergency.

If your rescue inhaler doesn’t help or you don’t have it with you, go to the emergency department if you have:

  • Anxiety or panic.
  • Bluish fingernails, bluish lips (in light-skinned people) or gray or whitish lips or gums (in dark-skinned people).
  • Chest pain or pressure.
  • Coughing that won’t stop or severe wheezing when you breathe.
  • Difficulty talking.
  • Pale, sweaty face.
  • Very quick or rapid breathing.

A note from Cleveland Clinic

Many people live fulfilling lives with asthma. Some professional athletes with asthma have set records in their sport. Your healthcare provider can help you find the best way to manage your asthma. Talk to your healthcare provider about how to control your symptoms.

Last reviewed by a Cleveland Clinic medical professional on 04/15/2021.


  • American College of Asthma, Allergy and Immunology. Asthma 101. ( Accessed 4/10/21.
  • American Lung Association. Asthma Symptoms, Causes and Risk Factors. ( Accessed 4/10/21.
  • Centers for Disease Control and Prevention. Asthma. ( Accessed 4/10/21.
  • Centers for Disease Control and Prevention. Most Recent National Asthma Data. ( Accessed 4/10/2021.
  • National Heart, Lung and Blood Institute. Asthma. ( Accessed 4/10/2021.

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