OncoLink

Managing Symptoms: Mouth Sores


What are mouth sores?

Mouth sores are small cuts or ulcers in the mouth. The sores may be bright red in color or have small white patches. Mouth sores may be painful.

Call your doctor or nurse if you have:
  • Painful areas in your mouth (lips, gums, tongue, roof of mouth and inside your cheeks)
  • Redness or shiny areas in the mouth
  • Difficulty eating or swallowing
  • Cracks, ulcers, blisters, white patches in the mouth
  • Temperature above 100.5º degrees, chills or sweats

What can I do?

  • Check your entire mouth daily (lips, gums, tongue, roof of mouth and inside of cheeks) using good lighting and a mirror. If you wear dentures, remove them and look under the plates.
  • Brush your teeth after eating or at bedtime:
  • Gently brush the teeth with a soft nylon bristle toothbrush. If this is painful, use foam toothettes or wrap gauze around a Popsicle® stick. Gently swab the teeth and gums.
  • Rinse your toothbrush well after each use. Store in a cool, dry place.
  • Use a non-abrasive toothpaste or solution of 1 teaspoon salt in 2 cups water.
  • Avoid toothpaste that contain additional ingredients such as whiteners or alcohol.
  • Keep lips moist with K-Y® jelly or Chapstick®. Do not use Vaseline®.
  • Avoid products that may dry the mouth, irritate the mouth and gums, or cause pain and discomfort, such as:
  • Commercial mouthwashes that contain alcohol
  • Lemon or glycerin swabs
  • Smoking
  • Alcohol
  • Chewing tobacco
  • Do not use dental floss.
  • Use a cool mist humidifier at night while sleeping.
  • Take pain medication 15-30 minutes before eating.

Take special precautions if you have dentures. Remove and clean dentures after each meal and at bedtime with a denture cleaner.

  • Remove dentures whenever possible to expose the mouth and gums to air.
  • Do not wear loose-fitting dentures that may irritate the mouth and gums.
  • If mouth sores are severe, do not wear dentures.
Gently rinse mouth before and after meals and at bedtime with one of the following:
  • Commercial mouthwash without alcohol or
  • 1 teaspoon baking soda in 2 cups water or
  • 1/2 teaspoon salt, 1 teaspoon baking soda and 1 cup water; or
  • 1 part hydrogen peroxide to 3 parts water.

Swish the solution in your mouth for 1-2 minutes and spit out.

Eat a healthy diet:

  • Drink 6-8 glasses of fluids a day.
  • Include foods high in protein such as dried beans, poultry, eggs, peanut butter, meat, fish, milk, cheese and yogurt.
  • Eat 6 meals a day, instead of 3 large meals.
  • Eat moist/soft foods.
  • Use liquid nutritional supplements.
  • Use mild sauces and gravies.
  • Avoid hot, spicy, greasy or fried foods.
  • Avoid citrus fruits and juices and tomatoes. Try apricots, pears or peaches instead.
  • Avoid hard or rough foods such as crusty breads, crackers, raw vegetables, potato chips, tortilla chips and pretzels
  • Avoid carbonated beverages, such as seltzers or soda.

What causes mouth sores?

  • Diseases of the head and neck
  • Some chemotherapy drugs
  • Radiation therapy, to the head and neck
  • Infections of the mouth
  • Some medications
  • Dehydration
  • Poor mouth care
  • Oxygen therapy
  • Poor nutrition

How are mouth sores treated?

Treatment of mouth sores will depend on their cause. Your doctor or nurse may recommend some of the following:

  • Putting Maalox or Milk of Magnesia on your mouth sores (see box below for instructions).
  • Rinsing mouth with 1 teaspoon of Kaopectate®, then spit out.
  • Prescription medications for infections in the mouth area.
  • Prescription pain medication.
  • Prescription medications to numb the mouth.

If your doctor or nurse tells you to use Maalox or Milk of Magnesia (MOM) on your mouth sores:

  • Pour Maalox or MOM into small cup
  • Allow to rest for 2 minutes
  • Pour the liquid off the top, until the chalky part remains
  • Use a q-tip and dip into the chalky part.
  • Gently swab the mouth sores with the q tip.
  • After 15 to 20 minutes, rinse with warm water.

Do not take any medications unless instructed by your doctor or nurse.

If you have any questions about mouth sores or need additional information, ask your doctor or nurse. Please let your doctor or nurse know if you need information on other topics.