I agree about the VG -- I have asthma, and as little as 30% VG just shuts my lungs down almost completely. I'd say try something more like 75%PG/25%VG and see if that helps. Or if you want to stay at 50/50, add 20% distilled water to thin it down. VG is just too thick for some people's lungs, especially people who already have compromised airways.
Andria
Same problem here and only use juice with 10-20% VG. In the last year I've seen ALL the doctors, i.e. primary, cardiologist, lungs, eyes, kidneys, sleep, etc. due to my overall health and for me this is the only way I can still vape.
Do see your doctor about your condition but bear in mind they also have their own opinions about vaping just like the rest of the world. My bottom line is this is the only thing that keeps me off cigarettes for years now. vaping looks like smoking which is what a lot of people are having trouble with but they will not consider the very important differences which in my mind are all positive.