Ozij... that's something to think about. I have a nazal mask and yes, I've awakened and had my mouth open. Hummmm... so the headaches could be due to "bad therapy" ...

WOW... I'm glad that there are people like you who are informed about this issue... this is all new to me... it's like learning another language with all the terms LOL

Jules, thank you, I will definately ask my doctor. Makes you wonder, why not prescribe the top of the line? This is all new to me and need all the information I can get. I just saw some videos on my machine (once I figured out which one I really had LOL) and I see where the filters are.