Asthma - Peak Flow Diary

This leaflet is designed to be printed out for people to record their peak flow reading.

We are holding off reviewing this leaflet until the SIGN guidelines on asthma are published, due October 2014.

A separate leaflet called Asthma - Peak Flow Meter describes how a peak flow meter is used, and why peak flow readings are useful, both to diagnose and to monitor asthma.

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, then 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.

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.

Below is an example of a two-week diary of peak flow readings done by a child who has quite bad asthma.

peak flow
Original Author:
Dr Tim Kenny
Current Version:
Document ID:
4684 (v39)
Last Checked:
Next Review:
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