My personal experience with cannabis and Asthma.

Well, i used to smoke cigs, and i've recently quit. When i was smoking cigs my breathing would be bad, and i'd weeze, but with weed i didnt, it stopped the weezing. And with a mate of mine, who has asthma, he said it can stop him having an attack, almost instantly after the first hit.

They're just my personal experiences with it.