Mouth sores are like little cuts or ulcers in the mouth. The sores may be very red, or may have small white patches in the middle. They may bleed or become infected. They can appear 1 to 2 weeks after some kinds of chemo. They can also be caused by radiation treatments to the head and neck area, infection, dehydration, poor mouth care, oxygen therapy, alcohol or tobacco, not getting enough vitamins, or lack of protein. Healing may take 2 to 4 weeks. Mouth sores can be very painful and lead to dehydration, poor eating, and weight loss. (See the section on fluids and dehydration.)

What to look for

• Inside of mouth and gums look red, shiny, or swollen
• Blood in mouth
• Small ulcers or sores in mouth, on gums, or on or under tongue
• A white or yellow film in the mouth or on the tongue
• Soreness or pain in mouth or throat
• Feeling of dryness, mild burning, or pain when eating hot and cold foods
• Soft whitish patches or pus in the mouth
• Increased mucus in the mouth

What the patient can do

• Check mouth twice a day using a small flashlight and a padded Popsicle stick. If you wear dentures, take them out before you inspect your mouth. Tell your doctor or nurse if your mouth looks or feels different or if you notice changes in how things taste.
• Follow the plan below for mouth care 30 minutes after eating and every 4 hours while awake, or at least twice a day unless your doctor or nurse gives you other instructions:

Brush your teeth using a soft nylon bristle toothbrush. To soften the bristles even more, soak the brush in hot water before brushing and rinse brush with hot water during brushing. If the toothbrush hurts, use a Popsicle stick with gauze wrapped around it or a cotton swab instead. Or you can get soft foam mouth swabs from the drugstore.

Rinse toothbrush well in hot water after use and store in a cool, dry place.

Use a non-abrasive toothpaste that contains fluoride. Note that whitening toothpastes may contain hydrogen peroxide, which can irritate sore mouths.

Remove and clean your dentures between meals on a regular time schedule. If you have sores under your dentures, leave your dentures out between meals and at night. Clean dentures well between uses, and store them in an anti-bacterial soak. If your dentures fit poorly, do not use them during treatment.

• Gently rinse your mouth before and after meals and at bedtime with one of the following solutions (Stir or shake the solution well, then swish it around and gently gargle, then spit it out.):

Or

• If you normally floss, keep flossing at least once a day unless you are told not to do so. Tell your doctor if this causes bleeding or other problems. If you do not usually floss, talk with your doctor before you start.
• Avoid store-bought mouthwashes, which often contain alcohol or other irritants.
• Keep lips moist with petroleum jelly, a mild lip balm, or cocoa butter.
• Drink at least 2 to 3 quarts of fluids each day, if your doctor approves.
• If mouth pain is severe or makes it hard to eat, ask your doctor about medicine that can be swished 15-20 minutes before meals or painted on a painful sore with a cotton swab before meals. If this does not work, you may need stronger pain medicines.
• To promote healing, ask your doctor about using Maalox ^® or Milk of Magnesia^®. You can use these products to help sores by allowing them to settle and separate, pouring the liquid off the top of the solution, and then swabbing the pasty part onto the sore area with a cotton swab. Rinse your mouth with water after 15-20 minutes.
• Sip warm tea slowly.
• Eat chilled foods and fluids (for instance, Popsicles, ice cubes, frozen yogurt, sherbet, or ice cream).
• Eat soft foods that are moist and easy to swallow.
• Eat small, frequent meals of bland, moist, non-spicy foods. Avoid raw vegetable and fruits, and other hard, dry, or crusty foods, such as chips or pretzels.
• Avoid very salty or high-sugar foods.
• Avoid acidic fruits and juices, such as tomato, orange, grapefruit, lime, or lemon.
• Avoid fizzy drinks, alcohol, and tobacco.
• Create a pleasant mealtime atmosphere.

What caregivers can do

• Use a flashlight to check the patient's mouth for red areas or white patches, which often become sores. If patient wears dentures, remove them before looking.
• Offer liquids with a straw, which may help bypass the sore area in the mouth.
• Mash or puree hard foods in a blender to make them easier to eat.
• Try coating mouth sores with Anbesol^® before meals to numb the sores during eating.
• Offer pain medicines a half hour before mealtime.

Call the doctor if the patient:

• Has redness or shininess in mouth that lasts for more than 48 hours
• Has bleeding gums
• Notices any type of "cut" or sore in the mouth
• Has a temperature of 100.5° F or higher when taken by mouth
• Has white patches on the tongue or inside the mouth
• Has taken in little food or fluid for 2 days
• Cannot take medicines due to sores in mouth

Go back to Caring for the Patient with Cancer at Home: A Guide for Patients and Families.

Last Medical Review: 04/27/2009
Last Revised: 04/27/2009