I have had exercise induced asthma since I was 6. I find that running doesn't make it any worse than other forms of exercise, but I can't go anywhere without my inhaler!
I've got a good asthma nurse (and I've read up quite a bit for myself), and I'm on the gold standard therapy, which is a Symbicort inhaler for prevention (combined fluticasone and formoterol - steroid and long-acting reliever) which has made a huge difference, and a bricanyl turbohaler, which is terbutaline (same as ventolin). The turbohalers are quite handy, as they're smaller than normal inhalers. You twist them to release the drug, then inhale through it (so no propellants needed). I'm very lucky that these work really well for me, and my asthma isn't brittle. I usually take my reliever before I set out for a run, then will probably use it once or twice in the first 10 minutes, and that's normally all I need.
I'm actually running the Brighton Half Marathon next weekend in aid of Asthma UK. I thought I'd chose a charity that has a direct impact on my life.
How do other people get on?