Sleeping on your back, by contrast, may reduce drooling for some people. In this position, gravity generally helps keep saliva inside the mouth, making it less likely to leak onto your pillow.
Mouth breathing is another common factor. A blocked or stuffy nose caused by allergies, a cold, or congestion can force you to breathe through your mouth, increasing the likelihood that your mouth will remain open during sleep.
Certain conditions, including acid reflux, may also contribute to increased saliva production. Your body can produce extra saliva to help protect and lubricate the throat, which may lead to more noticeable drooling overnight.
Occasional drooling is generally nothing to worry about. However, a sudden and persistent increase, difficulty swallowing, choking during sleep, or other unusual symptoms deserves medical attention. Otherwise, waking up with a little drool is simply a normal consequence of a relaxed body and peaceful sleep.
