It consists in the involuntary release of passive saliva through the mouth due to the inability to treat oral secretions.
This is not caused by an increase in the production of saliva that has actually decreased, but due to the gradual paralysis and lack of coordination of the muscles related to the orofacial and palatolingual area during the production of saliva.
Sialorrhea is normal in infants and young children. Mild to moderate drooling may continue in childhood and has been reported in children up to 5 years of age. The salivation or drooling beyond this period is generally considered pathological and is more common in patients with neurological disorders.
It is often exacerbated by dental malocclusion, poor oral closure, psychogenic control of the oral cavity, and limited control of the head or trunk related to neurological malfunction.
For example, hypersalivation is reported in 10% to 37% of children with cerebral palsy. The management of the sialorrhea is recommended when it represents some kind of clinical implications in a patient.
Hypersalivation or hypersalivation can be part of many diseases. It is often part of Parkinson’s disease, as it has an excessive production of saliva in combination with a reduction in swallowing.
Other neurological conditions can also cause hypersalivation, such as cerebral palsy, cerebrovascular conditions, traumatic brain injuries or neurodegenerative diseases such as ALS.
Some of the commonly observed symptoms are:
- Dysphagia .
- Change in the sense of taste.
- Grouping of saliva in the mouth.
Sialorrhea can be induced by certain types of medications. These drugs are called sialogogues and are sometimes prescribed to increase the production of saliva due to several side effects of these medications.
The drugs act on the parasympathetic nervous system, which is the part of the nervous system that increases salivation.
Few of the drugs can cause sialorrhea by direct stimulation of the brain and irritation caused in the oropharyngeal region. Some of these medications include pilocarpine, potassium chlorate, risperidone, ketamine, and clozapine.
A tonsillar abscess and infectious mononucleosis are also some of the few causes that lead to the drooling of saliva. Sometimes, salivation may be the only symptom until the other symptoms become prominent.
Local factors that cause sialorrhea include different varieties of stomatitis, acute necrotizing ulcerative gingivitis, and erythema multiforme. Older people who wear dentures (denture stomatitis) and those who can not practice good dental hygiene on their own may be at risk.
Systemic diseases involved in excessive secretion of saliva include paralysis, Parkinson’s disease, epilepsy and alcoholic neuritis. The condition is also common in neuromuscular disorders or followed by head trauma or stroke.
Metallic poisons that can induce increased salivation include mercury, copper and arsenic. Organophosphorus poisoning can also cause sialorrhea.
Mild to moderate sialorrhea may be associated with mild irritation by mouth or problems adapting dental prostheses or orthopedic appliances.
Episodic sialorrhea may be a treacherous manifestation of a gastroesophageal reflex (GERD). Increased salivation occurs as a protective mechanism to buffer in patients with GERD. This is called impetuous water.
A similar state of saliva whose underlying cause is unknown called idiopathic paroxysmal salivation. The increase in salivary flow consists of episodes that occur 1 or 2 times a week for 2-5 minutes.
The episodes are preceded by a multiple symptomatic response consisting of nausea or pain in the epigastrium, but without progressive vomiting.
These could be variants of the same clinical problem. Hypersalivation may also be associated with obstruction of the esophagus (foreign body, cancer and stenosis ), infection and nasogastric intubation.
Specific treatment for salivation is not always necessary unless the patient dribbles excessively or chokes on saliva. Patients should be encouraged to swallow more often to remove saliva from the mouth. Local factors that increase salivation, such as dental problems, should be corrected accordingly.
Medications used to treat sialorrhea include anticholinergic medications such as atropine sulfate. These drugs act on the parasympathetic nervous system and control the secretion of saliva. The drug is contraindicated in patients with asthma and glaucoma .
Glycopyrrolate and botulinum toxin A can also be used. Surgery is considered in patients with cognitive delay and profuse drooling.
Sialoreia is socially uncomfortable and can interfere with oral hygiene and is a risk factor for bronchial aspiration. The increased control of saliva can be done with chewing gum or hard candy to induce swallowing.
If this is not enough, toxin injections such as botulinum help to improve this socially uncomfortable condition. Botulinum toxin injections are considered effective only in the treatment of hypersalivation or hypersalivation related to Parkinson’s.