While its not a pill, I do take a twice daily Flovent inhaler for asthma. I hate having something that I have to have with me all the time, but its better than not breathing...because I know that sucks.
I started this recently, and I've had pretty good results. Now I don't hit the Albuterol inhaler every 4 hours like I was doing. My asthma has always come and gone, so that for years I didn't need anything, but now I have to have an inhaler with me all the time. It makes it a b*tch to exercise, because even before I get hot or sweaty, I can't breathe. And forget running outside, I couldn't even last a quarter mile.
Also, I would take Allegra, but insurance won't cover it now because there is a similiar over the counter medicine. Unfortunately, it is drastically inferior to Allegra, and I can't even notice any effects.