Excess saliva. Excess saliva, usually with drooling, is not very common in young people, but becomes more common in older folks. It can be caused by discoordination in the pharynx (not swallowing saliva), medications that stimulate salivary glands, conditions that stimulate the GI tract (vomiting, severe heartburn, esophageal spasm), and in older people, weakness of the oral muscles & lips, which leads to leakag.
Multiple reasons . Oral appliances such as dentures, night guards, orthodontic appliances, snoring & sleep apnea appliances can all cause temporary excess saliva. Mouth sores and acute inflammation may be a factor. Other factors could be alcoholism, malnutrition and certain mental retardation cases.