What causes drooling?

Drooling, or the involuntary outflow of saliva, may be caused by various factors.

1. Physiological causes are commonly seen in infants and young children, whose shallow and small oral cavities combined with underdeveloped swallowing functions often result in drooling.

2. Pathological causes might involve oral diseases such as mouth ulcers, gingivitis, etc., in which pain stimulates increased salivation; or neurological disorders such as Parkinson's disease and stroke, which can impair swallowing function.

3. Side effects of certain medications or improper sleeping positions may also lead to drooling.

4. Inflammation within the body, excessive internal heat (a concept in traditional Chinese medicine), deficiency of trace elements, or incorrect tooth brushing methods may also cause drooling.

If drooling is not physiological and occurs along with other symptoms, the patient should seek medical attention promptly.