• Incomplete swallowing (rather than not swallowing at all)
• Difficulty moving saliva to the back of the throat
• Poor mouth closure, sometimes because of incorrect positioning of the teeth
• Jaw instability
• Tongue thrusting

Some conditions can make drooling worse.   

• A lack of head control and poor posture
• Lack of sensation around the mouth
• Mouth breathing
• Excitement and impaired concentration
• Medications for other conditions, such as seizures, may aggravate drooling

Drooling can lead to children being socially ostracized, and there are also health and hygiene implications.  The skin around the mouth, chin, and neck can become red and sore.  Children may become dehydrated because of fluid loss.  There may be problems with eating.  Infections may be more easily transmitted.  The children are also more likely to inhale saliva, which can lead to infection and pneumonia.

In young children, creative use of bibs can keep their clothing from becoming soaked.  Children can also be taught to wipe their mouths frequently (assuming they are physically able).  Bibs should not be used when the neck is chafed.

A speech therapist can help by teaching a child how to work the mouth and tongue better.  Then the child can push saliva back toward the throat where it can be swallowed.

There are medications that can help control drooling.  These medications can have side effects.  There are also surgical techniques that involve rerouting of salivary ducts and removal of salivary glands.  If lack of head control is making drooling worse, correcting the sitting position so that the head is not hanging forward can lessen drooling.

No one technique for controlling drooling is currently found to be better than the others.  The use of behavior modification, sometimes along with medication, is generally recommended before using a surgical solution.  Surgery is not always successful.