Thanks everybody for the advice! I will take measures to make the air "cleaner" in the bedroom. I changed all my hoses/nasal pillows/filters/water (yes, i use distilled) out last night and I had a much better night. Wore it all night, no coughing.

I have been waking up at night a couple of hours after wearing my cpap, coughing. My throat and mouth so dry that it makes me gag. I have severe allergies, on meds and take shots. Anything helpful for this problem? I'm not congested in either chest or nasal passage.
Thanks