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Asthma: Measuring Peak Flow

Introduction

As someone with asthma, you know how important it is to monitor your condition. You need to know how well your lungs are "working." Is their ability to move air in and out staying the same, or is it getting better or worse?

When you monitor your asthma, you can control it. When you control your asthma, you also control your life—you do what you want to do, and your asthma does not limit you.

Measuring your peak expiratory flow is an important part of monitoring your asthma.

How To

If you have never used a peak flow meter, talk with your doctor about how to use it correctly, and then practice using it.

Measure your PEF regularly, even if you are feeling good. PEF is lowest in the early morning and highest in the afternoon. When you measure your PEF once a day, it needs to be done first thing in the morning before you use your asthma medicine.

It's very important to record the results of your PEF measurements in your asthma diary. This will help you notice changes in your breathing. Take your asthma diary with you when you see your doctor so you can review it together. It's very important to review the diary with your doctor whenever you feel your lung function is getting worse.

Measuring your peak expiratory flow

Remove any gum or food you may have in your mouth. Then use your peak flow meter to:

Measure your peak expiratory flow.

After you have blown into the meter 3 times, take the highest number you received, and write it in your asthma diary or on another record sheet.

If you cough or make a mistake during the testing, do the test over.

Different brands of meters may give different values for results. If you change meters, you will need to determine your asthma zones using the new meter.

Note: If your best effort is in your red zone, take your relief medicine immediately and call your doctor or go to the emergency room.

Credits

By Healthwise Staff
John Pope, MD - Pediatrics
Lora J. Stewart, MD - Allergy and Immunology
Last Revised March 14, 2013

Last Revised: March 14, 2013

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