Dry mouth (xerostomia) occurs when the salivary glands do not make enough saliva (spit) to keep the mouth moist. Because saliva is needed for chewing, swallowing, tasting, and talking, these activities may be more difficult with a dry mouth.

Causes

Dry mouth can be caused by chemotherapy or radiation treatments, which damage the salivary glands. Dry mouth caused by chemotherapy makes saliva thicker, causing the feeling of a dry mouth. This is usually temporary and normally clears up about two to eight weeks after treatment ends.

Radiation treatment to the head, face, or neck can also cause dry mouth. It can take six months or longer for the salivary glands to start producing saliva again after the end of treatment. Although some people experience improvement in their dry mouth during the first year after radiation treatment, many people will continue to experience some level of dry mouth indefinitely. This is especially true if the radiation therapy was directed at the salivary glands.

Dry mouth and mouth sores can also be caused by graft-versus-host disease, a disease in which bone marrow or stem cells attack the person’s own tissues as a result of a bone marrow or stem cell transplantation. In addition, some types of medications, including antidepressants, diuretics (medication that increases urination), and some painkillers, can cause dry mouth. Dry mouth can also be the result of a mouth infection (such as a fungal infection) or dehydration.

Signs and Symptoms

• Sticky, dry feeling in the mouth
  
  
• Thick, stringy saliva
  
  
• Pain or a burning sensation in the mouth or on the tongue
  
  
• Cracks in the lips or at the corners of the mouth
  
  
• A dry, tough tongue
  
  
• Difficulty chewing, tasting, or swallowing
  
  
• Difficulty talking
  
  
• Difficulty wearing dentures
  
  
• Mouth sores or mouth infections
  
  
• Tooth decay

Problems Associated with Dry Mouth

In addition to difficulty with eating and talking, dry mouth can cause dental problems. Saliva helps maintain a balance of bacteria in the mouth and protects against infections and cavities (tooth decay). Without enough saliva, the bacteria and other organisms in the mouth can grow too quickly, causing infections and mouth sores. Saliva also washes away acids and food particles left in the mouth after eating. Therefore, a lack of saliva can cause cavities and gum disease.

Management

Although dry mouth cannot be prevented, a couple of treatments can help. People receiving radiation treatment to the head or neck may be prescribed amifostine (Ethyol), a radioprotectant medication (medication that prevents or lessens the side effects of radiation treatment) that can reduce the severity of dry mouth. In addition, an investigational treatment in which a salivary gland is moved (transplanted) out of the field of radiation is being tested for some people. The following tips may help with the management of dry mouth and the prevention of dental problems.

• Visit a dentist at least two weeks before starting radiation treatment or chemotherapy to check the health of your mouth and teeth.
  
  
• Brush your teeth at least four times a day with a soft-bristle toothbrush and fluoride toothpaste; soak the brush in warm water to make the bristles even softer.
  
  
• Floss gently once a day.
  
  
• Rinse your mouth four to six times a day, especially after meals, with a solution of salt and baking soda (½ teaspoon of salt and ½ teaspoon of baking soda in 1 cup of warm water).
  
  
• Drink sips of water throughout the day and use artificial saliva to moisten the mouth.
  
  
• Chew sugarless gum or suck on sugarless candies to help increase saliva flow.
  
  
• Avoid mouthwashes and other dental products that contain alcohol; products designed especially for people with dry mouth are available without a prescription.
  
  
• Use a cool mist humidifier, especially at night.
  
  
• Some dentists may also prescribe a fluoride gel to apply at bedtime, prescription medication to increase saliva production, or rinses to fight infections in the mouth.

Tips for Eating with a Dry Mouth Include the Following:

• Drink at least eight cups of water a day; consider carrying a bottle of water.
  
  
• Avoid alcohol, drinks with caffeine (coffee, tea, cola), and acidic juices.
  
  
• Eat soft, moist foods that are cool or at room temperature.
  
  
• Moisten dry foods with broth, sauces, butter, or milk.
  
  
• Avoid dry, coarse, or hard foods.
  
  
• Avoid acidic or spicy foods that burn the mouth.
  
  
• Do not smoke or chew tobacco.
  
  
• Avoid sticky, sugary foods and drinks.

More Information

Difficulty Swallowing (Dysphagia)

Taste Changes

Dental Health during Cancer Treatment

Managing Side Effects

Last Updated: February 27, 2009