Xerostomia is the medical term for a dry mouth due to a lack of saliva.  It can be caused by medications, radiation, illness, or normal aging.  Xerostomia can cause difficulty with speech and eating. It can also lead to halitosis (bad breath) and a dramatic rise in the number of cavities, as the protective effect of saliva's remineralizing the enamel is no longer present.  Xerostomia can make the oral tissues of the mouth more vulnerable to infection.

Causes

It may be a sign of an underlying disease, such as Sjögren's syndrome, poorly controlled diabetes, or Lambert-Eaton syndrome, but this is not always so.  Other causes of insufficient saliva include anxiety, medications, or the consumption of alcoholic beverages, physical trauma to the salivary glands or their ducts or nerves, dehydration caused by lack of sufficient fluids, excessive breathing through the mouth, previous radiation therapy, and also a natural result of aging, other conditions or factors not mentioned also can have the ability to cause dry mouth. The vast majority of elderly individuals will suffer xerostomia to some degree. Playing or exercising a long time outside on a hot day can cause the salivary glands to become dry as the bodily fluids are concentrated elsewhere. Xerostomia is a common side-effect of various medications and drugs.

Treatment

Treatment involves finding any correctable causes and fixing those if possible. In many cases it is not possible to correct the xerostomia itself, and treatment focuses on relieving the symptoms and preventing cavities. Patients who have endured chemotherapy usually suffer from this post- treatment. Patients with xerostomia should avoid the use of decongestants and antihistamines, and pay careful attention to oral hygiene. Sipping sugarless fluids frequently, chewing  xylitol-containing gum, and using a carboxymethyl cellulose saliva substitute as a mouthwash may help. Aquoral may be prescribed to treat xerostomia. Non-systemic relief can be found using an oxidized glycerol triesters treatment used to coat the mouth. Drinking water when there is another cause of the xerostomia besides dehydration may bring little to no relief and can even make the dry mouth more uncomfortable.

Xerostomia Information Links

Drymouth.info - Detailed Database on medications that cause Dry Mouth

Xerostomia (Dry Mouth). Causes, symptoms & health risks - Treatments & natural remedies

Oral Cancer Foundation

University of Illinois at Chicago

NIH

Sjögren's Syndrome Foundation page on Dry Mouth

Biotene and Oral Balance Products

Much of the information on this page has come from Wikipedia^®