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Learning About Peak Flow Meters

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A peak flow meter is a device used to measure peak flow. Peak flow is how much air you breathe out when trying your hardest. Checking your peak flow can tell you how well your lungs are working. It helps you know if your asthma is staying the same, getting better, or getting worse.

Peak flow meters come in many shapes and sizes, but they work about the same. Follow these steps to measure your peak flow.

Three different peak flow meters set to their lowest number.

1. Set the pointer of the peak flow meter to 0 or the lowest number on the meter.

A mouthpiece and a peak flow meter.

2. If there is a separate mouthpiece, attach it to the meter.

A person taking a deep breath to get ready to use the peak flow meter.

3. Sit up or stand up as straight as you can. Take a deep breath.

A person with a peak flow meter mouthpiece in their mouth.

4. Close your lips tightly around the mouthpiece. Keep your tongue away from the mouthpiece. Keep your fingers away from the number scale.

A person breathing out hard into the peak flow meter.

5. Blow out as hard and as fast as you can.

Three peak flow meters with different results.

6. Note the number on the meter, and write it down. Do the test 2 more times. The highest of these 3 tests is your peak flow.

Follow these tips to use peak flow to help manage asthma.

  • Find your personal best peak flow. Keep a diary of your peak flow when your asthma is under control. Your doctor will let you know how long to do this. Your personal best peak flow is the highest number in your diary.

  • Work with your doctor to make an asthma action plan. Your doctor will add peak flow numbers to each zone in your action plan. The numbers are based on your personal best peak flow.

    • You're in the green zone when your peak flow number is close to your personal best. It's where you want to be.
    • You're in the yellow zone when your peak flow number is much lower than your personal best. Your asthma may be getting worse.
    • You're in the red zone when your peak flow number is very low. It means danger. Get medical help.

  • Check your peak flow, and find which zone you're in. Or you can use your symptoms along with your peak flow to find the zone you're in. Check your peak flow as often as your doctor recommends.

  • Follow the steps in your action plan for the zone you're in. This can include what medicine to take and when to call for help.

  • Recheck your personal best peak flow now and then. Ask your doctor how often to recheck it. If it has changed, the numbers on your action plan may need to be changed.

Where can you learn more?

Go to http://www.healthwise.net/patientEd

Enter R965 in the search box to learn more about "Learning About Peak Flow Meters".

Current as of: July 31, 2024

Author: Ignite Healthwise, LLC Staff

Clinical Review Board
All Healthwise education is reviewed by a team that includes physicians, nurses, advanced practitioners, registered dieticians, and other healthcare professionals.

Current as of: July 31, 2024

Author: Ignite Healthwise, LLC Staff

Clinical Review Board
All Healthwise education is reviewed by a team that includes physicians, nurses, advanced practitioners, registered dieticians, and other healthcare professionals.

The Health Encyclopedia contains general health information. Not all treatments or services described are covered benefits for Kaiser Permanente members or offered as services by Kaiser Permanente. For a list of covered benefits, please refer to your Evidence of Coverage or Summary Plan Description. For recommended treatments, please consult with your health care provider.