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.
Drooling associated with fever or trouble swallowing may be a sign of a more serious disease including:
A sudden onset of drooling may indicate poisoning (especially by pesticides) or reaction to snake or insect venom or in some cases of a numbed mouth from either orajel, or when going to the dentist office. Some medications can cause drooling as well such as the pain reliveing orajel medication. Some neurological problems also cause drooling. Excess Capsaicin can cause drooling as well, an example being the ingestion of particularly high Scoville Unit chili peppers.
Another form of ptyalism is associated with pregnancy, most common in women with a condition known as Hyperemesis Gravidarium, or uncontrollable and frequent nausea and vomiting during pregnancy which is far worse than typical "morning sickness". With Hyperemesis, ptyalism is a side-effect, which is a natural response to uncontrollable vomiting. With normal vomiting, salivary glands are stimulated to lubricate the esophagus and mouth to aid in expelling of stomach contents. During a hyperemetic pregnancy, many woman complain of excessive saliva and an inability to swallow this saliva. Some women note having to carry around a "spitoon" or using a cup to spit. Swallowing their own saliva has been noted to gag and further nauseate the women making the hyperemesis that much worse.
There are several theories as to the causes of hyperemesis and related symptoms such as ptyalism. Although hyperemesis was once considered a psychological disease, the medical community now considers hyperemesis as a real and serious physiological condition. Some pregnant women who suffer end up terminating the pregnancy. Others refuse to carry another child. The most frequent act is preparing for the onset of hyperemesis if a subsequent pregnancy is expected.
Drooling also is common in children with neurological disorders and those with undiagnosed developmental delay. The reason for excessive drooling seems to be related to (1) lack of awareness of the build-up of saliva in the mouth, (2) infrequent swallowing, and (3) inefficient swallowing. Treatment of excessive drooling is related to these causes: (1) increased awareness of the mouth and its functions, (2) increased frequency of swallowing, (3) increased swallowing skill.
It may be more common when resting soon after meals.