Tests for Asthma Severity Levels

If you think you might have asthma, there are several tests available to help your doctor diagnose and determine severity. Consult your healthcare provider and they can either perform diagnostic tests themselves or refer you to a specialist such as an allergist/immunologist or pulmonologist.

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Diagnosing Asthma

A common sign of asthma is wheezing—a whistling sound that occurs while breathing. If you’re experiencing symptoms such as wheezing, frequent cough, shortness of breath, or chest tightness, you should get tested for asthma right away. Not all asthma is alike, and symptoms vary among sufferers, so your doctor will discuss your medical history with you as a way of helping to identify your asthma triggers and your overall exposure to them.


Find an Asthma Specialist

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Physical Exam

Your doctor or asthma specialist will run you through a series of tests to help determine what kind of asthma you may have and establish the best course of treatment.

An Exam May Include:
  • A review of your family history of asthma, allergies, or sensitivities
  • A discussion about your symptoms
  • A check of your lungs for wheezing that could indicate inflammation in your airways
  • An exam of your nose and throat for excess swelling and drainage issues
  • An X-ray of your lungs and sinuses
  • Additional tests to rule out other conditions
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Lung Function Tests

There are a number of breathing tests that are used to measure lung and breathing functions in patients. The two below, however, are among the more common tests.

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Spirometry measures how much air you can quickly and efficiently cycle through your lungs. It’s performed by placing a clip on your nose as you breathe into the spirometry machine. It’s safe, painless, and can be conducted right in your doctor’s office.

What It Tests
  • How much air you can inhale
  • How much air you can exhale, and how quickly
  • How fast you can empty your lungs of air
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Peak Flow Meter

A peak flow meter is a handheld device and is used for taking daily measurements of your breathing. It’s an essential tool for keeping track of your symptoms and is available over-the-counter. Consult your doctor or asthma specialist to help you find the right one for you.

What It Determines
  • How easily you expel air from your lungs
  • If your breathing changes from day to day
  • Which steps to follow on your Asthma Action Plan
  • When to adjust your medicine use and dosage, including your rescue medicine, per your healthcare provider's instructions
  • When to seek emergency care
Graph: Asthma Peak Flow Numbers

Tracking Your Peak Flow Numbers

When tracking your numbers, log the HIGHEST of three readings. This is known as your personal best number and, when logged, should include the date and time of the reading. Your doctor may recommend this be done daily.

Track Your Asthma

Image: Asthma Patient Checking Peak Flow

Your Asthma Action Plan may advise how often to check peak flow readings:

The Asthma Action Plan you establish with your doctor may tell you to take your peak flow reading more often and to adjust your medicines.

Learn More About Asthma Action Plan