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Learning About Asthma

Lungs in chest showing bronchial tubes, with detail of healthy airway and airway narrowed by asthma

What is asthma?

Asthma is a chronic disease that affects your breathing. It causes the airways that lead to the lungs to swell.

People with asthma may have asthma attacks. During an asthma attack, the airways tighten and become narrower. This makes it hard to breathe, and you may wheeze or cough. If you have a bad asthma attack, you may need emergency care.

Asthma affects people in different ways. Some people only have asthma attacks during allergy season, or when they breathe in cold air, or when they exercise. Others have many bad attacks that send them to the doctor often.

What are the symptoms of asthma?

When you have asthma, you may:

  • Wheeze, making a loud or soft whistling noise when you breathe in and out.
  • Cough a lot. This is the only symptom for some people.
  • Feel tightness in your chest.
  • Feel short of breath. You may have rapid, shallow breathing or trouble breathing.
  • Have trouble sleeping because you're coughing or having a hard time breathing.
  • Get tired quickly during exercise.

Symptoms may start soon after you're around things (triggers) that cause your asthma attacks.

Symptoms can be mild or severe. You may have symptoms daily or just now and then. Or you may have something in between.

Some people have symptoms that get worse at night, such as a cough and shortness of breath.

How can you prevent asthma attacks?

Certain things can make asthma symptoms worse. These are called triggers. When you are around a trigger, an asthma attack is more likely.

Common triggers include:

  • Cigarette smoke, vapour, or air pollution.
  • Things you are allergic to, such as:
    • Pollen, mould (including snow mould), or dust mites.
    • Pet hair, skin, or saliva.
  • Illnesses, like colds, flu, or pneumonia.
  • Dry, cold air.

Here are some ways to avoid a few common triggers:

  • Do not smoke or vape, or allow others to smoke or vape around you. If you need help quitting, talk to your doctor about stop-smoking programs and medicines. These can increase your chances of quitting for good.
  • If there is a lot of pollution, pollen, or dust outside, stay at home and keep your windows closed. Use an air conditioner or air filter in your home. Check your local weather report or newspaper for air quality and pollen reports.
  • Get the flu vaccine every year. Talk to your doctor about getting a pneumococcal shot. Wash your hands often to prevent infections.
  • Avoid exercising outdoors in cold weather. If you are outdoors in cold weather, wear a scarf around your face and breathe through your nose.

How is asthma treated?

There are two parts to treating asthma, which are outlined in your Asthma Action Plan. The goals are to:

  • Control asthma over the long term. Your Asthma Action Plan tells you which medicine you may need to take every day. This is called a controller medicine. It helps to reduce the swelling of the airways and prevent asthma attacks.
  • Treat asthma attacks when they occur. Your Asthma Action Plan tells you what to do when you have an asthma attack. It helps you identify triggers that can cause your attacks. You use quick-relief medicine during an attack.

The Asthma Action Plan also helps you track your symptoms and know how well the treatment is working.

Follow-up care is a key part of your treatment and safety. Be sure to make and go to all appointments, and call your doctor or nurse call line if you are having problems. It's also a good idea to know your test results and keep a list of the medicines you take.

Where can you learn more?

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