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Symptoms and Diagnosis

Asthma symptoms

Different people have different asthma symptoms, which can change over time or depending on the situation. Common asthma signs and symptoms include:

  • Feeling short of breath (at rest or when exercising)
  • Chest tightness
  • Coughing
  • Wheezing

These symptoms can also be caused by other conditions. If you have these symptoms or if you think you might have asthma, see your doctor for a proper diagnosis.

Asthma symptoms – childhood vs. adult

Childhood asthma symptoms are generally similar to adult asthma symptoms. However, determining asthma symptoms in children can be a bit more difficult. Adult asthma symptoms are easier to determine since an adult can tell you how they are feeling plus they know their body better. Although you can see and hear the coughing and shortness of breath (laboured breatthing, faster breath rate) in younger children, they may not be able to let you know how they are feeling. Plus young children are not able to do a breathing test called spirometry.

Some things you may notice in your child that could indicate asthma include:

  • Not being able to keep up with other children while running around
  • Having a hard time catching their breath or breathing faster than other children who are doing the same thing
  • Looks like they have a cold, which could actually be asthma
  • Coughing, especially at night
  • Coughing so hard that they vomit
  • You may hear wheezing (high pitched whistling sound)
  • If you notice any of these typical childhood asthma symptoms, see your doctor to find out if it is due to asthma.

Asthma symptoms – acute vs. chronic

In medical related matters, “acute” simply means short term, and “chronic” means long term. Although asthma is a chronic disorder, since it usually lasts a long time (often a lifetime), you can have both chronic and acute asthma symptoms. If someone does not properly manage their asthma, they can have regular chronic symptoms for many weeks, months, or even years. For example, they could experience a regular cough that lasts a long time if not managed properly.

Then on top of the regular chronic cough, they may also sometimes experience an acute asthma worsening that leads to a symptom such as shortness of breath. This could perhaps be due to getting a cold, or exposure to pollen or air pollution.

When someone has asthma, it is very important to keep it well controlled so that there are no chronic asthma symptoms. You can’t avoid all asthma symptoms all the time, but in general the symptoms should be uncommon and mild.

It is also very important to monitor your asthma so that you notice when there are acute asthma symptoms starting and can take the necessary measures to get it under control before it leads to an asthma attack. A written asthma action plan from your doctor can be very helpful in guiding your treatment decisions.


If you think you might have asthma, it is important to get a proper diagnosis. Once asthma is diagnosed, it is possible to manage it well so that you can live a full active life. There are many people who have asthma but do not know they have it. The diagnosis of asthma is based on many factors including:

  • Medical history
  • Physical examination
  • Test results, such as a lung function test

Medical History

Your medical history includes any past and current health issues that could be related to your asthma. Your health-care provider will ask you about:

  • Your medical history and your family medical history (e.g., allergies, eczema, hay fever)
  • What symptoms you have had and for how long
    • Have you had a cough? Shortness of breath? Chest tightness? Wheeze?
    • Do you have these symptoms at night or in the early morning hours?
    • Do you get symptoms when you exercise, have a cold, or are exposed to cold air?

Physical Examination

A physical exam includes checking for signs that you might have asthma. Your health-care provider will:

  • Examine your chest and breathing rate
  • Use a stethoscope to listen to your lungs for unusual sounds while you breathe
    • Examine your nasal passages for signs of allergies
    • Examine your skin for signs of eczema

Lung Function Tests

Lung function tests (breathing tests) such as spirometry are an important part of diagnosing asthma.

  • Spirometry testing involves taking in a deep breath and breathing out as hard and long as you can into a tube. Once all your air has been exhaled, you then inhale as fast and deep as you can until your lungs are totally full. This test measures important flows and volumes and compares them to normal values.
  • Spirometry testing is often done before and after using a reliever inhaler (bronchodilator) to see if there is a change in your lung function
  • People under six years of age are not usually able to do a spirometry test

If your spirometry test results are normal but your health-care provider still thinks you might have asthma, you may be sent for further testing. A “challenge test” using either methacholine or histamine can also help diagnose asthma.

Allergy Testing

Your health-care provider may refer you to an allergist for an allergy assessment. This may include an allergy skin test that tests you for reactions to specific allergens (e.g., pets, dust mites, pollen, mould). This can help you find out what allergens may be causing your asthma symptoms.
An allergy skin test involves placing drops of allergens on your forearm or back and making small scratches in the skin where the drops are located. The amount of redness and swelling caused by these allergens will help to show if you have any allergies.

Trial of Asthma Medications

Your health-care provider may prescribe asthma medications for you to take to see if they improve your asthma symptoms. If asthma medications improve your symptoms, this increases the likelihood that you have asthma.

Other Tests

Chest x-rays are not very useful in the diagnosis of asthma, but they may help rule out other reasons for your symptoms.

A blood test or sputum (phlegm, mucus) test may sometimes be ordered.

Diagnosing Asthma in Young Children

Diagnosing asthma in a young child can be more challenging because:

  • Children under six years of age are not generally able to do a lung function test
  • Symptoms such as cough and wheeze are fairly common in very young children who do not have asthma

However, a diagnosis of asthma can be made in a young child. Your health-care provider will assess:

  • What symptoms does the child have?
  • When do the symptoms occur (e.g., seasonal, during colds)?
  • Is there a history of allergies or asthma in the family?
  • Does the child have any signs of allergies (e.g., congested nose, eczema)
  • Do the symptoms improve when taking asthma medications?

For more information please call 1-888-344-LUNG (5864) or email info@lungontario.ca.