It makes me wonder if the propellants themselves were the more active ingredient and not the chemicals propelled by the propellants...I mean it shouldn’t matter by what means the chemicals get in....but if the inhalors worked better with the old propellants then perhaps the propellants should be looked at as possible treatments for common lung ailments!
The propellants have no effect on the lungs.
The issue is/was the proper delivery of the correct amount of the active ingredients.
I suppose that’s possible. Whatever the new propellants are, though, they don’t propel much.