Finding drool on your pillow when you wake up might feel embarrassing, but it is actually a common and usually harmless part of sleeping. For most people, occasional drooling simply reflects what happens to the body as it relaxes during sleep.
As you drift into deeper sleep, many muscles throughout your body become more relaxed. This includes the muscles involved in controlling your jaw, mouth, and swallowing reflex. As a result, your mouth may open slightly while you are asleep.
At the same time, your swallowing becomes less frequent. Saliva
