Drooling – with a focus on cerebral palsy

From Scope website: Drooling beyond infancy may occur in some medical conditions such as when there is inflammation of the mucous membranes of the mouth or as a reaction to some medications, which cause an increase in the amount of saliva produced.

In some conditions including cerebral palsy, drooling is usually related to:

abnormalities in swallowing - rather than to absence of swallowing
difficulties moving saliva to the back of the throat
poor mouth closure
jaw instability
tongue thrusting

Drooling is not usually caused by an excess of saliva as is sometimes thought. Instead it has been found that there is a tendency to swallow less frequently than normal.

Drooling can be made worse by a lack of head control and poor posture, lack of sensation around the mouth, breathing through the mouth, excitement and impaired concentration.