Drooling all the time may be caused by drugs, or gastroesophageal reflux, peripheral facial paralysis and other diseases. 1. Drugs: If the patient has recently taken anti-psychotic, cholinergic agonists and other drugs, causing cholinergic nerve excitation, it will increase salivary secretion, and the performance of drooling all the time. 2. Gastroesophageal reflux: the occurrence of this disease is related to the decrease of esophageal clearance, the impairment of anti-reflux function and the decrease of esophageal mucous membrane resistance, etc. The patients will have reflux, heartburn, belching (hiccups) and other symptoms, and when the food is blocked, it will stimulate the salivary secretion through the esophageal-salivary reflex to make the salivary secretion increase, and it may be manifested as drooling all the time. 3. Peripheral facial paralysis: the common cause of this disease is idiopathic facial nerve paralysis, followed by trauma, such as temporal bone fracture, surgical injuries, etc., which can be triggered by cold stimulation, viral infections, etc., resulting in patients with drooling all the time, crooked corners of the mouth, and the eyes can not be closed and other symptoms. In addition, drooling all the time also needs to be considered as a result of diseases such as pulpitis, Parkinson’s disease, arteriosclerosis, and so on. It is recommended that patients with constant drooling go to the hospital for a complete examination to clarify the specific cause.