Oncologist-approved cancer information from the American Society of Clinical Oncology
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Dry Mouth or Xerostomia

This section has been reviewed and approved by the Cancer.Net Editorial Board, 1/2012


Xerostomia (dry mouth) 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.

Signs and symptoms

The signs and symptoms of dry mouth include the following:

  • A 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

In addition, dry mouth often causes dental problems. Saliva helps maintain a healthy balance of bacteria in the mouth. Without enough saliva, the bacteria and other organisms in the mouth grow too quickly, causing mouth infections and sores. Saliva also washes away acids and food particles left in the mouth after eating, which means that a lack of saliva can cause cavities (tooth decay) and gum disease. Dry mouth may make it difficult to wear dentures, as well.


Chemotherapy or radiation treatments cause dry mouth by damaging the salivary glands. Chemotherapy causes dry mouth by making saliva thicker—usually a temporary symptom that clears up about two to eight weeks after treatment ends.

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

In addition, graft-versus-host disease (a disease in which cells transplanted from a donor recognize the patient's body as foreign and attack it) may cause dry mouth and mouth sores. Some types of medications—including antidepressants, diuretics (medications that increase urination), and some painkillers—cause dry mouth. Or, dry mouth can result from a mouth infection (such as a fungal infection) or dehydration.

Managing dry mouth

Relieving side effects—also called symptom management, palliative care, or supportive care—is an important part of cancer care and treatment. Talk with your health care team about any symptoms you experience, including any new symptoms or a change in symptoms.

Although dry mouth cannot be prevented, some treatments can help. These include:

  • Radioprotectant medication (medication that prevents or lessens the side effects of radiation treatment), such as amifostine (Ethyol)
  • Saliva substitutes and mouth rinses with hyetellose, hyprolose, or carmellose
  • Medications that stimulate the salivary glands, such as pilocarpine (Salagen) or cevimeline (Evoxac)
  • Other ways to stimulate the salivary glands, such as sucking on sugar-free candy or chewing sugarless gum

Additionally, a small clinical trial suggested the acupuncture might help with dry mouth, although these results are preliminary.

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 (a half teaspoon of salt and half teaspoon of baking soda in one cup of warm water).
  • Drink sips of water throughout the day, and use artificial saliva to moisten the mouth.
  • Avoid mouthwashes and other dental products that contain alcohol. Products designed for people with dry mouth are available without a prescription.
  • Use a cool mist humidifier, especially at night.

In addition, some dentists may prescribe a fluoride gel to apply at bedtime, prescription medication to increase saliva production, or rinses to fight infections in the mouth.

Consider the following tips for eating with a dry mouth:

  • Drink at least eight cups of water a day. Carrying a bottle of water may help you drink enough.
  • Avoid alcohol, drinks with caffeine (such as coffee, tea, and 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 or Dysphagia

Taste Changes

Managing Side Effects

© 2005-2014 American Society of Clinical Oncology (ASCO). All rights reserved worldwide.

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