Exercise-induced asthma, and very bad sinus allergies. I use a neti-pot twice a week; I'd use it more, but my referring to it as the "home waterboarding kit" probably tells you why I don't. It's effective, but I just can't get used to the feeling of it. Anyhow....
Chemically, I'm using Nasonex and Astepro twice a day to dry up the running sinuses. I take a single puff from my Ventolin before any ride, and I carry it with me in case I need it.
For very long rides (5+ hours) I'll take a 10mg ephedrine (no guiafenesin) before the ride, and one more every 5 or so hours if needed to keep things opened so I can breathe.
__________________
"I feel like my world was classier before I found cyclocross."
- Mandi M.