Asthma can cause inflammation of the lungs and airways. As a result, a person may experience symptoms including coughing, wheezing, chest tightness, and shortness of breath. They may also experience changes in the structure of the lungs.

Doctors diagnose asthma by considering a person’s medical history, performing physical exams, and using lung function tests to measure how well they are working. Chest X-rays are a valuable screening tool for people with asthma, but doctors do not use them alone to diagnose the condition.

Asthma may also lead to changes in breathing patterns and sounds. Some people tend to produce a wheezing sound when having an asthma attack.

Keep reading to learn more about how asthma affects the lungs.

A person holding a black and white sketch of the lungs in front of their chest 1Share on Pinterest
RubberBall Productions/Getty Images

Chest X-rays typically present nonspecific findings in people with asthma. However, doctors may use them to rule out other conditions that could be causing asthma-like symptoms, such as a foreign body or pneumonia.

In general, X-ray imaging shows the following changes in asthma lungs:


Hyperinflation occurs when the air becomes trapped in the lungs and causes them to appear larger. It may happen due to blockages or if the air sacs — alveoli — are less elastic and do not expel air from the lungs as they should.

Bronchial wall thickening

This is a typical response to irritants that enter the airway and indicates that the bronchi — a passageway in the lungs — are inflamed or swollen. It may appear as hazy areas on the image.

Although X-rays have many advantages, doctors are generally moving away from them for routine asthma care.

Chest CT scans may provide more detailed images of the lungs in people with asthma.

For example, CT scans may show the following:

  • bronchial wall thickening
  • air trapping, which are pockets of “extra” air stuck in the lungs
  • changes in the structure of the bronchioles, which are smaller branches that the bronchi expand into

Similarly to X-rays, these scans can help exclude other conditions.

Learn more about how doctors diagnose asthma.

When someone has asthma, their lungs may produce a wheezing sound when they breathe in and out. Narrowed airways and restricted air movement through the lungs may be responsible for the wheezing sound.

The sound can be continuous or come in multiple short bursts, depending on asthma severity. However, if the person has severe bronchoconstriction — squeezing of airways — the wheezing sound may not always be audible. This is likely due to significantly limited airflow.

With severe asthma, the breathing-out phase is longer. The breathing in and breathing out ratio is at least 1:3, meaning that for every second the person breathes in, they breathe out for 3 seconds.

In comparison, lungs without asthma produce no audible wheezing, and the breathing-in and breathing-out phases are of equal length.

People with asthma may experience:

The symptoms usually come and go and worsen with exposure to certain triggers, such as allergens, exercise, or cold air.

Asthma can also cause fatigue. This is likely because the inflamed airways make breathing harder than usual, so more effort is necessary to move air in and out of the lungs. People with asthma may feel anxious due to difficulty breathing and may take longer to rest after strenuous physical activity.

Severe asthma attacks may cause extreme difficulty breathing and require emergency medical treatment.

Asthma and allergy resources

To discover more evidence-based information and resources for living with asthma and allergies, visit our dedicated hub.

Was this helpful?

If a person experiences an asthma flare-up, they should try to remove or move away from the trigger.

Doctors often recommend medications to reduce inflammation in the lungs and keep them as clear as possible. These can include:

A combination of the medications above may help someone achieve clear lungs.

In some cases, doctors need to adjust or change asthma treatments if they are not managing symptoms effectively.

Asthma is a chronic condition that can cause irreversible lung damage if it is difficult for a person to manage. There is currently no cure. However, with medications and lifestyle changes, it may be possible to:

  • reduce inflammation
  • relieve bronchospasms effectively
  • prevent permanent or further damage to the lungs and airways

Learn more about action plans for managing asthma.

Doctors do not diagnose asthma with an X-ray alone. However, it is a useful tool for identifying underlying conditions, and there are visible changes in some cases.

On an X-ray, asthma lungs can appear with hazy areas that indicate inflammation and thickening of the bronchial walls. People with asthma may feel tightness in the chest, shortness of breath, coughing, and wheezing.

Asthma is a chronic condition, but it is possible to reduce inflammation and manage symptoms with medications and lifestyle.