i used to take singular for my asthma before they started advertising it as an 'allergy' medication. it worked extremely good, as a maintanance drug, NOT for fast-acting needs, like asthma attacks. it worked so well, i rarely needed my
proventil (albuterol) inhaler, which i was using at least a few times a day. i became pregnant and had to stop it, and haven't gone back to it since my asthma's somewhat under control now with
advair. but as far as the singular goes, it's excellent for helping an asthma patient feel like they don't have asthma.
hope that helped. i'd be happy to answer any other asthma questions or concerns you may have, as i've been on literally everything under the sun for my asthma (my dad's a pharmamcist, and he used to bring home samples for me of just about everything when i was a child.) as an adult, i've been under doctor care my whole life and have used many drugs thru him as well.
good luck...
by the way, what would you be switching
from?