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Signs and symptoms of asthma


To make a diagnosis of asthma the doctor will:

Take a detailed medical history. Your doctor will ask detailed questions about your family medical history, your breathing problems, and other asthma symptoms you might have.

Do a physical examination: The doctor will listen to your lungs with a stethoscope; examine your nasal passages, etc.

Test your breathing with spirometry. Spirometry is a quick, simple breathing test that measures how much air you can blow out of your lungs. This might be done in a hospital or in your doctors' office. For this test, you'll be asked to blow hard and long through a tube attached to a small machine. The machine will show how many litres of air you can push out of your lungs and how fast. Because spirometry takes some coordination, children under 5 years old are not usually asked to do this test.

Find a lung function testing lab in your area, using our online database.

Your doctor may also order other tests:

  • Chest x-ray
  • Lab tests on your blood and sputum (phlegm, mucus)
  • Allergy testing: Your doctor may refer you to an allergist, who will test you for specific allergies, ask what your symptoms are and when you notice them. Usually allergists use a skin prick test. This may help to find out what allergies makes your asthma worse.
  • Challenge tests: These tests are done in a hospital. They help to tell the doctor how "twitchy" or hyper-responsive your airways are.

Trial of asthma medications: The doctor may give you asthma medications to try out. If the asthma medications make your symptoms go away, this may help to make the diagnosis of asthma.

With a proper diagnosis, your doctor and asthma healthcare team can help you manage your asthma.

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