Causes of Dry Mouth
Dry Mouth conditions range from very minor problems caused by over use of the
voice or nervous tension, to total shut down of the saliva glands. Saliva has
many functions. It lubricates the ingested foods and protects mucous membranes
from irritation and toxic substances. The flow of saliva aids in removing materials
from the mouth in a cleaning action. It maintains a neutral pH. thereby limiting
the acid producing effect of the breakdown of sugars on the teeth and development
of tooth decay. Saliva also has antibacterial and coagulation properties.
Salivary gland dysfunction (Dry Mouth) can be caused by local glandular effects
or systemic disease. In terms of local glandular effects, two Dry Mouth conditions
may arise: hyposalivation (moderate) or xerostomia (severe). The result is difficulty
in chewing, swallowing and digesting food. The most prevalent forms of xerostomia
are found in cancer patients taking radiation treatments. Especially those with
cancer in the neck and head area.
Systemically, Sjorgren's Syndrome is the most prevalent cause
of xerostomia. It is a chronic inflammatory autoimmune disease in which the
body's exocrine secretions - the eyes, nose, mouth and vagina - dry up. Other
systemic diseases such as sarcoidosis, cystic fibrosis, hormonal dysfunction
(thyrotoxicosis and diabetes), seleroderma, hypertension, obesity, hyperlipidemia
alcoholic cirrhosis, malnutrition and lichen planus are all associated with
xerostomia. Additionally, it is estimated that 25% of the elderly and 10% of
AIDS patients suffer from xerostomia.
Any drug that causes a decrease in blood flow to the salivary
glands will lessen salivary secretions:
Anti hypertensives that lower blood pressure will decrease blood
flow
Diuretics that decrease blood flow by decreasing blood volume
affect blood
flow to the salivary glands.
Some specific drugs cause dry mouth (xerostomia):
e.g. isotretinoin (Accutane), gemfibrozil (Lopid), anti-inflammatories
(NSAIDS), antineoplastics (Matulane, Myleran), anti-ulcer (Carafate), calcium
supplement Neo Calglucon), antinauseants (Reglan), and nicotine patches.
Of the 25 most frequently prescribed drugs in 1992, the following
drugs are associated with xerostomic side effects:
Zantac (ranitidine)
Xanax (alprazolam)
Seldane (terfenadine)
Naprosyn (naproxen) Prozac (fluoxetine)
Proventil (albuterol)
Tagamet (cimetidine)
Dyazide (triameterene)
Hydrochlorthiazide
In addition to prescribed medication,
at least half of the doses ingested in the U.S. are over-the-counter drugs.
Of those drugs, the most frequently used medications that have xerostomic side
effects are as follows:
Laxatives - Chronulac, Phospho-Soda Antinauseants - Dramamine
Cold and Allergy products
antihistimines Anti-diarrheals - loperamide
Other drugs may also have xerostomic properties:
tobacco
marijuana
cocaine heroin
amphetamine
