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Coping with mouth sores from cancer treatment


12 ounces of warm water, ¼ teaspoon baking soda and ¼ teaspoon salt

People with mouth sores can use a rinse made from 12 ounces of warm water, ¼ teaspoon baking soda and ¼ teaspoon salt.


What they are:

Mouth sores that develop during chemotherapy and/or radiation treatment are called “oral mucositis.” They look like burns. Often they appear on the inside lining of the mouth or lips. You may notice them on your gums, tongue or the roof or floor of your mouth. They may also appear on the esophagus, the tube your food travels into the stomach.

Whether they form depends on the type and dose of chemotherapy you are taking, or the area and dose of radiation delivered if you are taking radiotherapy.

How they form:

Many cancer treatments are designed to kill rapidly growing cells. Cancer cells grow rapidly, but so do the cells that line the inside of your mouth. When these healthy cells are damaged, mouth sores may develop. This can range from a minor inconvenience to a severe complication that could impede eating, talking, swallowing and even breathing.

Why they matter:

Untreated, mouth sores can lead to infection, painful ulcers or the inability to eat and drink, and cancer treatment can be affected.

How they‘re treated:

Doctors can prescribe medications that coat the entire lining of the mouth, so the sores are protected and the pain is lessened. Topical painkillers may be used for numbing.

What you can do:

  • Make sure your dentist is aware you will be undergoing chemotherapy or radiation therapy and ask about taking care of any unresolved dental issues such as gum disease, cavities or teeth that need to be pulled.

  • Tell your doctor if you have a history of mouth sores. Antiviral medicines are sometimes prescribed for people who get frequent mouth sores from the herpes simplex virus.

  • Floss with caution. If you have dentures, clean them at least once a day, wear them only when necessary and make sure they fit properly.

  • Rinse your mouth frequently while awake and if you awaken during the night. Use a solution of 12 ounces of warm water, ¼ teaspoon baking soda and ¼ teaspoon salt.

  • Brush your teeth with a soft-bristle brush after every meal, using a non-irritating toothpaste as recommended by your dentist.

  • Check your mouth three or four times a day for sores or any changes – and keep your doctor posted.

  • Keep your lips and mouth moist. Drink 1 to 2 liters of fluid per day. Use a lip moisturizer. Suck on sugar-free candy or chew gum. Popsicles or ice can help decrease swelling and reduce pain. Consider using a saliva substitute.

  • Liquid Tylenol or Advil may help relieve mouth pain. Your doctor or nurse can recommend prescription options if necessary.

  • Maintain good nutrition, eating foods and liquids that are easy to swallow. Cut your food into small pieces. Or, you may need to use a blender to mix your food with a liquid.

  • Foods high in protein are the best choice. You may also include daily servings of liquid supplements such as Ensure, Boost or Carnation Instant Breakfast. Seek a referral to a nutritionist if you would like help.

What you should not do:

  • Do not assume you can crush medication if you are having trouble swallowing. Speak to your pharmacist first.

  • Do not use alcohol-based mouthwashes, which can dry out your mouth.

  • Do not use alcohol, caffeine and tobacco, as these can cause your mouth to dry out.

  • Do not eat extremely hot or cold foods or fluids, and avoid foods that are spicy or contain citric acid to avoid mouth irritation.

  • Do not eat foods that are hard, crunchy or chewy because they can irritate your mouth.

Fall 2016 issue of Cancer Care magazineThis article appears in the fall 2016 issue of Cancer Care magazine.