Mouth dryness or thick saliva

Radiation therapy to the head and neck areas, some types of chemo, and certain other medicines can cause dry mouth or thick saliva. The glands that make saliva can become irritated and make less saliva, or your saliva can become very thick and sticky. Dryness can be mild or severe.

A dry mouth can increase your risk of cavities and mouth infection. If you smoke, chew tobacco, or drink alcohol, the dryness can be worse.

If you have either of these side effects, drink plenty of fluids throughout the day and eat moist foods as much as possible. Also brush your teeth and rinse your mouth often with a baking soda, salt, and water solution to help keep it clean and prevent infection (recipe follows).

What to do

  • Drink 8 to 10 cups of liquid a day, and take a water bottle wherever you go. (Drinking lots of fluids helps thin mucus.)
  • Take small bites, and chew your food well.
  • Eat soft, moist foods that are cool or at room temperature. Try blenderized fruits and vegetables, soft-cooked chicken and fish, well-thinned cereals, popsicles, smoothies, and slushies.
  • Avoid foods that stick to the roof of the mouth like peanut butter or soft bread.
  • Moisten foods with broth, soup, sauces, gravy, yogurt, or creams.
  • Suck on sugarless candy or chew sugarless gum to stimulate saliva. Citrus, cinnamon, and mint flavors often work well.
  • Keep your mouth clean. Rinse your mouth before and after meals with plain water or a mild mouth rinse (made with 1 quart water, 1 teaspoon salt, and 1 teaspoon baking soda – shake well before using). Use a soft-bristle toothbrush. It’s a good idea to gently brush your tongue, too. Ask your doctor if it’s OK to floss.
  • Avoid commercial mouthwashes, alcoholic and acidic drinks, and tobacco.
  • Limit caffeine intake, from coffee, tea, energy drinks, and caffeinated soft drinks.
  • Use a cool mist humidifier to moisten room air, especially at night. (Be sure to keep the humidifier clean to avoid spreading bacteria or mold in the air.)
  • Fresh pineapple or papaya may help to thin saliva, but only try this if your mouth is not sore.
  • Saliva substitutes are helpful if your salivary glands have been removed by surgery or damaged by radiation therapy. These products add moisture to your mouth.
  • Nutritional supplements, like liquid meal replacements, may be helpful. If you can’t get enough calories and nutrition through solid foods, you may need to use liquid supplements for some time. Talk to your cancer care team about this.

What to eat or not eat when you have a dry mouth*

  Eat Foods that may cause problems
High protein

    Meats, poultry, and fish in sauces and gravies

    Casseroles, soups, and stews 

Dry meats, poultry, and fish without sauces 
Breads, cereals, rice, and pasta

    Bread, rolls

    Cooked and cold cereals, cereal with milk

    Rice soaked in gravy, sauce, broth, or milk 

    Dry breads, rolls

    Pasta, rice

    Pretzels, chips

    Dry cereal

Fruits and vegetables

    Canned and fresh fruits that have a lot of moisture, like oranges and peaches

    Vegetables in sauce

    Bananas, dried fruit

    Vegetables, unless in a sauce or with a high moisture content

Drinks, desserts, and other foods

    Club soda, hot tea with lemon (decaf), fruit-ades, diluted juices, sports drinks

    Commercial liquid nutrition supplements

    Homemade milk shakes; ice cream, sherbet, pudding

    Butter, margarine

    Salad dressing

    Sour cream, half-and-half 

Cookies, cake, pie, unless soaked in milk 

*Adapted from Eldridge B, and Hamilton KK, Editors, Management of Nutrition Impact Symptoms in Cancer and Educational Handouts. Chicago, IL: American Dietetic Association; 2004.

The American Cancer Society medical and editorial content team

Our team is made up of doctors and oncology certified nurses with deep knowledge of cancer care as well as journalists, editors, and translators with extensive experience in medical writing.

Last Medical Review: July 15, 2015 Last Revised: July 15, 2015

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