At the moment I'm trying out this treatment called the "EasySleep Pro Adjustable Stop Snoring Chin strap". I's basically a bit of headgear you wear while sleeping to stop yourself from snoring. I figured it might help with the lip drying out situation because it stops you from opening your mouth during the night. I have only been using it for a few days. It is not very comfortable but worth a try to see if it improves the lip situation.