possegal, that was a lot of very good information. You also said a lot of the same things my doc said so it seems you are very well informed in this area. Thank you so much for you input. I don't feel like I have stressed much at all about the nodule...it's more like I was just trying to educate myself about it as much as possible. But I know nothing really about PFTs and what the results mean. You helped clear that up. Do you think getting something like OTC Primatine Mist would help me determine if an inhaler would help with the breathing difficulties I'm getting while riding - or should I just call him and ask for an Rx? This all started when I started getting chest pains after a backpacking trip to Colorado. The CT scan of my heart showed the nodule in my lungs...that's the only way I found out about it. Otherwise I probably would have never known. I probably would have chalked up the breathing issues to just being "out of shape" ...even though riding should be getting easier not harder as time goes on.