Saliva in medicine called salivation, refers to saliva from the mouth to flow out of the mouth. Western medicine believes that salivation is divided into physiological and pathological. Physiological salivation is more common in children under 3 years old, mainly because the baby’s mouth is shallow, will not control oral saliva. In the neonatal period, salivary glands are not developed. After the fifth month, salivary secretion increases. At six months, due to the shade of teeth < / P > < p > in daily life, some people will salivate unconsciously at night, which may be a signal of some diseases. Although a small amount of saliva is still secreted continuously during sleep, under normal circumstances, people will not drool after sleeping. If drooling occurs during sleep, it may be due to incorrect sleeping posture. However, if this is the case for a long time, it may be caused by oral inflammation, facial neuritis and other diseases, and may also be the precursor of stroke. < / P > < p > oral inflammation can promote saliva secretion, cause pain and cause saliva flow. Generally speaking, after the treatment of inflammation, the phenomenon of salivation will disappear automatically; facial neuritis may also make people drool, which generally occurs after a person’s face is cold, windblown or cold, and such patients often have loose eyes If you suddenly drool after falling asleep, and smile in the mirror after getting up in the morning, you will find that the angle of your mouth is crooked, or you have headache and other symptoms, which means that the possibility of stroke is relatively large. In this case, the patient must not take it lightly, and should immediately go to the hospital for relevant examination to prevent the disease in the bud. < / P > < p > when people often drool, they must be alert to their own body, so that they can be found and treated early, and serious diseases will be nipped in the bud.