Drooling and bad breath at night in bed requires an analysis of the patient’s age, the length of the disease, and whether there are other accompanying symptoms. Take a young person with drooling as an example to illustrate, with long-term poor oral hygiene, the temperature and humidity inside the mouth is suitable for the reproduction of bacteria, because the food residue on the teeth and teeth surface, resulting in periodontitis or other dental diseases will cause drooling and bad breath. Consider also the age of the patient, for example, after the occurrence of cerebral infarction in the elderly, the accompanying symptoms in the appearance of limb movement dysfunction, crooked corners of the mouth at the same time, there may be clinical manifestations of drooling, while the patient is prone to halitosis due to poor digestion, oral hygiene and other factors, so once such clinical manifestations should be promptly to the hospital for reasonable diagnosis and treatment for the cause, to minimize the adverse Clinical consequences, resulting in personal life, work inconvenience.