From The Art and Popular Culture Encyclopedia
Drooling (also known as ptyalism or sialorrhea) is when saliva flows outside the mouth. Drooling is generally caused by excess production of saliva, inability to retain saliva within the mouth, or problems with swallowing.
Some people with drooling problems are at increased risk of inhaling saliva, food, or fluids into the lungs. However, this is unlikely to cause harm, unless the body's normal reflex mechanisms (such as gagging and coughing) are also impaired.