Using a Peak Flow Meter

A peak flow meter is a portable, easy-to-use device that measures how well your lungs are working. If you have asthma, your doctor may recommend that you use a peak flow meter to help track your asthma control.

In addition to watching for worsening signs and symptoms, such as wheezing or coughing, you can use a peak flow meter to help you decide when you need to act to keep your asthma under control. Regular use of your peak flow meter can give you time to adjust your medication or take other steps before your symptoms get worse. A peak flow meter can be useful for adults and children as young as preschool age.

Peak flow meters are available on NHS prescription in the UK. Some people may find it useful to have a peak flow meter to help them manage their asthma, so you could ask your doctor to prescribe one for you. You can also purchase one from a pharmacy.

There are several different makes of peak flow meter and two different types known as low and standard range.
Standard range peak flow meters are suitable for both adults and children. Low range peak flow meters are designed for adults with low readings, and for children.

Your doctor should normally state the make and type on your prescription, but the manufacturer of the peak flow meter is not important because they all do the same thing, which is measure your expiratory flow rate. In simple terms this means how hard and quickly you blow air out of your lungs.

The meter has a marker that slides up the scale as you blow out. The better controlled your asthma, the harder you will be able to blow out and the higher your peak flow score will be.

Peak flow readings are measured in litres per minute and it is important that you get to know your best peak flow.