How to use your peak flow meter

A peak flow meter helps you check how well your asthma is controlled. Peak flow meters are most helpful for people with moderate-to-severe persistent asthma.

How to measure your peak flow

First: Find your personal best

To find your "personal best" peak flow number, take your peak flow each day for 2 - 3 weeks. Your asthma should be under good control during this time. Take your peak flow as close to the times listed below as you can. These times for taking your peak flow are only for finding your personal best peak flow.

Write down the number you get for each peak flow reading. The highest peak flow number you had during the 2 - 3 weeks is your personal best.

Your personal best can change over time. Ask your doctor when to check for a new personal best.

Using your peak flow meter every day

Once you have established your personal best, take your peak flow at these times:

Check to see which zone your peak flow number is in. Take the actions your doctor told you to do in that zone, which is written in your action plan. If you use more than one peak flow meter (such as at home and at school), be sure that both meters are the same brand.

Created by the National Heart, Lung, and Blood Institute. Modified by A.D.A.M., Inc.

 


Review Date: 6/29/2012
Reviewed By: Allen J. Blaivas, DO, Clinical Assistant Professor of Medicine UMDNJ-NJMS, Attending Physician in the Division of Pulmonary, Critical Care, and Sleep Medicine, Department of Veteran Affairs, VA New Jersey Health Care System, East Orange, NJ. Review provided by VeriMed Healthcare Network. Previoulsy reviewed by David A. Kaufman, MD, Section Chief, Pulmonary, Critical Care & Sleep Medicine, Bridgeport Hospital-Yale New Haven Health System, and Assistant Clinical Professor, Yale University School of Medicine, New Haven, CT. Review provided by VeriMed Healthcare Network. (6/1/2010)
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