Dry mouth—also called xerostomia—results from an inadequate flow of saliva. It is not a disease, but a symptom of a medical disorder or a side effect of certain medications, such as antihistamines, decongestants, pain killers, diuretics and many others.

Saliva is the mouth’s primary defense against tooth decay and maintains the health of the soft and hard tissues in the mouth. Saliva washes away food and other debris, neutralizes acids produced by bacteria in the mouth and provides disease-fighting substances throughout the mouth, offering first-line protection against microbial invasion or overgrowth that might lead to disease.

Some of the common problems associated with dry mouth include a constant sore throat, burning sensation, trouble speaking, difficulty swallowing, hoarseness or dry nasal passages. In some cases, dry mouth can be an indicator of Sjögren’s (pronounced SHOW-grins) syndrome. Sjögren’s syndrome is a chronic autoimmune disorder in which the body’s immune system mistakenly attacks its own moisture-producing glands, the tear-secreting and salivary glands as well as other organs.

Without saliva, extensive tooth decay can also occur. Your dentist can recommend various methods to restore moisture. Sugar-free candy or gum stimulates saliva flow, and moisture can be replaced by using artificial saliva and oral rinses.