Peak Flow Meters and Your Peak Flow Rate

What is a peak flow meter used for?

They’re usually used by people with asthma to measure peak expiratory flow rate (PEFR or peak flow). PEFR is the maximum speed you’re able to use when blowing air out of your lungs.

Peak Flow Meters and Your Peak Flow Rate

Your doctor may recommend using a peak flow meter daily or several times a day, as part of a personalized asthma action plan for managing symptoms.

Peak flow meters have a mouthpiece you forcefully blow into with one powerful breath. The meter measures the force you expel air in liters per minute (L/m). An indicator on the meter moves in response to the force of your breath to a spot along a numbered scale.

Consistent use of a peak flow meter can help you keep track of how well asthma is being controlled. It can also help signal a change in a respiratory condition, such as COPD.

Keeping track of your readings can provide information that your asthma is getting worse or that a flare is coming. If your numbers decline, it can alert you that your airways have narrowed before you have asthmatic symptoms.

A peak flow meter can also help you and your doctor determine if your current treatment protocol is effective or needs to be changed.