They use PG in inhalers and inhalers save lives every day. I've been using prescription inhalers for asthma for over 25 years. The only side effect I've ever had is what I call 'inhaler heartburn' which can be completely avoided by not doing anything aerobic for at least 45 minutes to an hour after the last time I use it. I also vape and have not used an emergency inhaler since I quit smoking cigs. And I have found that for me at least, Nicotine is so much less addicting in vape juice. It really makes me wonder what the hell the tobacco companies are putting in their cigarettes to make them more addictive than heroin. And my Pulmonologist is so happy that I quit smoking that he wanted to know what vape I use so he could recommend it to other cigarette smokers who want to quit. It is Not the same as cigs AT ALL.