I've been running on a treadmill as a part of my work out routine. I've been doing this about 3-5 times a week and I tend to run a couple miles.

The reason I've been running indoors on a treadmill (other than the winter weather) is that I cannot seem to run outside. I can make it maybe 1/4 mile before I start coughing and if I continue I'll cough until it makes me sick.
I've had this problem for a while and when I told my doctor about it she cited exercise induced asthma and gave me an inhaler. I found that the inhaler didn't help which could be due to drinking water or general misuse I suppose. Mainly, I don't think it's asthma because I feel like I need to cough, but my airways are open (I can breath okay).
I've found the best thing to keep me from coughing is to take small sips of water but that make running outdoors pretty difficult.

Do any of you know what this problem could be? Anyone suffer from it? Ideas as to what I can do would be great!

Note: I do live at 7,000 feet elevation but I've had this problem at lower altitude as well.

Yeah, this happens to me too. It's primarily when I run in the cold. My solution is that I don't run :p.

I have no idea what causes it though.

If it happens only when you run in the cold, a balaklava or handkerchief can help by warming/moistening the air before it hits your throat and lungs. (And provide amusement as you watch the expressions of people taking in your bank-robber-ish appearance.)

If it happens during warm weather, then I have no input.

If it happens only when you run in the cold, a balaklava or handkerchief can help by warming/moistening the air before it hits your throat and lungs. (And provide amusement as you watch the expressions of people taking in your bank-robber-ish appearance.)

If it happens during warm weather, then I have no input.
Unfortunately, it does indeed happen in warm weather.