Drooling during sleep is common and usually harmless. However, it can sometimes indicate underlying issues. Here are some common causes:
1. Muscle Relaxation:During deep sleep, muscles, including those in the mouth and jaw, relax, causing the mouth to open and saliva to escape.
2. Sleeping Position:Sleeping on your stomach or side makes it easier for saliva to escape, while back sleepers tend to swallow more easily.