Peak flow diary
Peer reviewed by Prof Cathy Jackson, MRCGPAuthored by Dr Colin Tidy, MRCGPOriginally published 5 Jan 2018
Meets Patient’s editorial guidelines
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This leaflet is designed to be printed out for people to record their peak flow reading.
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Peak flow diary for printing off
To take a peak flow reading
Put the marker to zero.
Take a deep breath.
Seal your lips around the mouthpiece.
Blow as hard and as fast as you can into the device.
Note the reading.
Repeat three times.
The 'best of the three' is the reading to record on the chart.
What are normal and abnormal peak flow readings?
Normal peak flow readings vary, depending on your age, size, and sex. The range of normal peak flow readings is published on a chart, and doctors and nurses refer to the chart when they check your peak flow reading. In healthy people, peak flow readings vary slightly from time to time. The reading is often slightly higher in the evening compared with the morning.
Peak flow normal values
Below is an example of a two-week diary of peak flow readings done by a child who has quite bad asthma.
Peak flow graph
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About the authorView full bio
Authored by
Dr Colin Tidy, MRCGP
General Practitioner, Medical Author
MBBS, MRCGP, MRCP (Paediatrics), DCH
Dr Colin Tidy is an NHS Doctor, based in Oxfordshire.
About the reviewerView full bio
Prof Cathy Jackson, MRCGP
Medical Author
BSc (Hons) Physiology, MB, ChB, MRCGP, MD
Professor Cathy Jackson graduated from Manchester Medical School having gained a first-class honours degree in physiology along the way.
Article history
Article also available in English, German, Spanish, French, Italian, Portuguese, Hindi, Hebrew, Arabic, and Swedish.
5 Jan 2018 | Originally published
Authored by:
Dr Colin Tidy, MRCGPPeer reviewed by
Prof Cathy Jackson, MRCGP
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