Peak flow meters are very helpful if you or your child have moderate to severe asthma and require daily asthma medications. Even most children ages 6 and up should be able to use a peak flow meter ...

Peak flow monitoring usually is recommended for adults and children who are at least 5 and have moderate to severe asthma, or for those whose symptoms aren't under control and whose medication is ...

Record asthma symptoms and peak expiratory flow (PEF) readings Compare PEF readings ... Your doctor will also use this diary to evaluate how well your asthma action plan is working.