A: Some of the things that could cause dry mouth would be caffeine if you're consuming that, and potentially mouth breathing at night. There's a trend about mouth taping. I don’t know if you would consider it, but you can look it up and see if it could make a difference for you.
Also, for some people, there are different side effects of medications that can cause dry mouth. There could be a lack of hydration in your room. Some things like mold in your home can actually be one of the reasons for dry mouth as well. There's a whole host of different potential reasons, but I would start by limiting caffeine and see if that helps.