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Asthma Health Center

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Peak Flow Meters


© Healthwise, Incorporated

A peak flow meter is an inexpensive, pocket-size device that measures peak expiratory flow (PEF), or how much air a person can breathe out. To measure PEF, the person takes a deep breath and then blows into a tube on the peak flow meter as hard and as fast as possible. This can be done at home.

Peak flow meters come in many shapes and sizes.

ByHealthwise Staff
Primary Medical ReviewerJohn Pope, MD - Pediatrics
Specialist Medical ReviewerLora J. Stewart, MD - Allergy and Immunology

Current as ofSeptember 9, 2014

WebMD Medical Reference from Healthwise

Last Updated: September 09, 2014
This information is not intended to replace the advice of a doctor. Healthwise disclaims any liability for the decisions you make based on this information.

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