Asthma is a long-term condition in which the airways in the lungs become inflamed and narrow, making it hard to breathe. It affects children and adults, and symptoms can range from an occasional cough to life-threatening attacks. With the right treatment and a clear plan, most people with asthma can live active, normal lives.
What happens in asthma
In people with asthma, the airways are sensitive and often inflamed. When exposed to a trigger:
- The muscles around the airways tighten (bronchospasm).
- The airway lining swells.
- Extra mucus is produced.
Together, these changes narrow the airways and reduce airflow.
Common symptoms
- Wheezing, a whistling sound when breathing out
- Shortness of breath
- Chest tightness
- Coughing, often worse at night, early in the morning or with exercise
Symptoms may come and go. Some people have mostly a cough.
Common triggers
- Allergens: pollen, dust mites, mold, pet dander and cockroaches
- Respiratory infections, such as colds, flu and COVID-19
- Tobacco smoke, including secondhand smoke, and vaping
- Air pollution and wildfire smoke
- Cold, dry air
- Exercise
- Strong smells, such as perfumes and cleaning products
- Stress and strong emotions
- Certain medicines, including aspirin and other NSAIDs in some people, and some beta-blockers
- Workplace exposures, such as chemicals and dusts
How asthma is diagnosed
Your clinician will ask about your symptoms and family history and examine you. Tests may include:
- Spirometry: you breathe into a device that measures how much air you can blow out and how fast. Improvement after an inhaled bronchodilator supports a diagnosis of asthma.
- Peak flow monitoring at home to track changes.
- FeNO testing, which measures a marker of airway inflammation.
- Allergy tests to identify triggers.
Asthma treatment
Treatment aims to control symptoms, prevent attacks and keep lungs healthy. Most people use inhalers, and correct inhaler technique is essential.
Controller (maintenance) medicines
- Inhaled corticosteroids (ICS): the most effective long-term controllers. They reduce airway inflammation and the risk of severe attacks.
- Combination inhalers: an ICS with a long-acting bronchodilator (such as formoterol, salmeterol or vilanterol).
- Leukotriene modifiers, such as montelukast, taken as a tablet. They carry a warning about possible mood and behavior changes.
- Long-acting muscarinic antagonists, such as tiotropium, as an add-on.
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Reliever (rescue) medicines
- Short-acting bronchodilators, such as albuterol, quickly relax the airway muscles.
- ICS-formoterol as a reliever: many current guidelines, including the Global Initiative for Asthma, now prefer a combination inhaler containing an inhaled steroid and formoterol as the reliever for adults and teenagers, because it treats both narrowing and inflammation and lowers the risk of severe attacks. Using a short-acting reliever alone without a controller is no longer recommended for adults and adolescents with asthma.
Your clinician will choose the approach that fits your age, symptoms and history.
Biologic therapies
For severe asthma that is not controlled with inhalers, injectable biologic medicines that target specific parts of the immune response may be an option. A specialist will check whether you are a candidate.
Your asthma action plan
Everyone with asthma should have a written asthma action plan prepared with their clinician. It typically uses three zones:
- Green zone (doing well): no symptoms; take your usual controller medicines.
- Yellow zone (getting worse): coughing, wheezing, chest tightness or waking at night; follow the plan to step up treatment and contact your clinician.
- Red zone (medical alert): severe shortness of breath, reliever not helping, trouble walking or talking; use your reliever and call 911.
Signs of a severe asthma attack
Call 911 or go to the emergency department if:
- Your reliever inhaler is not helping, or you need it more than every few hours
- You are too breathless to speak in full sentences or walk
- Your lips or fingernails look blue or gray
- You are using neck and chest muscles to breathe
- Your peak flow is in the red zone
- You feel drowsy, confused or exhausted
Living well with asthma
- Take controller medicines every day as prescribed, even when you feel well.
- Check your inhaler technique with your clinician or pharmacist. Spacers help many people get more medicine into the lungs.
- Avoid or reduce triggers where possible.
- Do not smoke or vape, and keep your home smoke-free.
- Get vaccinated against flu, COVID-19 and pneumococcal disease as recommended.
- Stay active. With good control, most people can exercise; some use their reliever before exercise as advised.
- Review your asthma at least once a year, and after any attack.
The CDC and the National Heart, Lung, and Blood Institute have more resources.
Frequently asked questions
Can asthma be cured?
There is no cure, but asthma can be well controlled. Some children’s symptoms improve as they grow, though asthma may return later.
Are inhaled steroids safe?
At the doses used for asthma, inhaled steroids are considered safe for long-term use. Rinsing your mouth after use reduces the risk of hoarseness and thrush.
Can adults develop asthma?
Yes. Asthma can start at any age, including in adulthood.
The bottom line
Asthma is common and manageable. Learn your triggers, use your inhalers correctly, follow a written action plan and know the signs of a severe attack. Regular reviews with your clinician keep your treatment up to date.
This article is for general information and is not a substitute for advice from a qualified healthcare professional.