HFA Asthma Inhalers: Making the Switch
Deadline to make the transition to HFA inhalers is fast approaching. WebMD explains how HFA inhalers differ from CFC inhalers and how to make the changeover easier.
1. What are the differences between CFC and HFA inhalers?
The primary difference is the way albuterol is propelled from the canister into the lungs, but some patients will notice that the "blast" of spray is gentler with HFA devices.
"The feel is a little different, so if somebody is switching, if they're not aware that the HFA jet is more gentle, they might feel they're not getting the same amount. It's just as effective, but people's expectations need to match what they're receiving," says Martha White, MD, an allergist in Wheaton, Md.
Three of four inhalers available - Proventil HFA, ProAir HFA, and Ventolin HFA - dispense albuterol. The fourth HFA inhaler, Xopenex, carries levalbuterol -- another bronchodilator agent of the same class as albuterol. White says her patients on the Xopenex report that it feels "cleaner."
The HFA propellant also is "gummier" than the CFC propellant, so it's important to clean the plastic sleeve that holds the canister, ideally after each use, but at least once a week. Users may also notice a difference in taste.
HFA inhalers also need to be primed, or sprayed a few times in the air before using, according to guidelines from the American Academy of Allergy Asthma & Immunology.
2. Is one HFA inhaler more effective than another?
No. In studies with children and adults, the effects of HFA albuterol on lung function tests have been shown to be similar to CFC albuterol. With Xopenex HFA, some people get less jittery than with other albuterol inhalers, White tells WebMD. Ventolin HFA has a dose counter so you know how many doses are left, whereas Proventil HFA and ProAir HFA do not have dose counters.