I think we need to distinguish between emergency inhaler and inhalation therapy.

Some inhalers are emergency inhalers (albuterol, etc.) and intended to provide immediate relief during an asthma attack or to ward one off. I'll also use mine when I'm a little wheezy and anticipating that exertion might trigget an attack before a gym workout, fishing a trout stream or hiking.

Advair discs, synthetic steroid inhalers and others are meant to provide some sort of therapy to the lung or bronchia tissue and the relief doesn't occur until after the change prrovided by the therapy has taken place.

I've been to docs who simply say, "Inhaler, ty this for your asthma," without specifying what the purpose of the inhaler is. Up to us to read the fine print on the back side of the leaflet to find out what's going on, or press the doc for clear instruction on what it's for.