What is important in measuring peak flow?

Your physician is only interested in the HIGHEST peak flow value achieved during a measurement session. Please repeat the measurements until you feel you have gotten the best possible result for that session. In the event of declining results at each successive measurement, talk to your doctor. It may be a sign of unstable asthma.

Coughing during a measurement can produce erroneously low results so always repeat the measurement. If you want to perform continuous measurements sequentially, be sure to have sufficient relaxation after each measurement to ensure accurate results.

Please note that low peak flows indicate a pending asthma attack even though no symptoms are felt!