I have noticed that I wake up with a very pasty (in fact sticky) mouth when waking up after using the machine. It feels like my tongue and mouth are stuck together with a light glue. A little water gets rid of he feeling. When I don't use the machine (I didn't take it on my recent Red Cross tour in New Orleans), I don't get that problem.
This is different from the dry mouth feeling one gets when sleeping with the mouth open.
JohnP

