Chemotherapy can damage the cells lining the mouth, throat, and gastrointestinal tract. This damage is called mucositis. Mucositis affects the mouth as painful mouth sores, called stomatitis. This side effect is common with certain chemo drugs and can be very painful.

Diagnosis

Symptoms typically start around 5 to 10 days after the start of chemotherapy. Mouth sores, also called ulcerations, may feel hot and look red. Your tongue may swell and look as if it has a coating on it. In some cases, your doctor may reduce your planned chemo dose. Talk to your doctor and care team if you think you have mouth sores.

Treating mouth sores is important because:

  • Pain from mouth sores may make it difficult to eat, talk, or swallow
  • Open sores may allow bacterial, fungal, or viral organisms to enter the body and cause infection
  • Mouth sores can lead to treatment interruptions

Causes

Certain factors are known to increase the chances of getting mouth sores:

  • Poor oral health prior to and during treatment
  • Having other diseases in addition to cancer

What You Can Do

  • Do not use mouthwashes with alcohol. Rinse out your mouth several times a day with a cup of warm water mixed with 1/4 teaspoon baking soda and 1/8 teaspoon salt. Then rinse your mouth out with plain water.
  • Brush your teeth, tongue, and gums gently with an extra-soft toothbrush after every meal and at bedtime.
  • Sucking on ice chips before and during your chemotherapy treatment may help prevent mouth sores in some patients getting certain types of chemo. This technique is called cryotherapy.
  • There are special mouthwashes that may be available by prescription only. Ask your doctor if a prescription rinse would help treat your mouth sores.

Ask your doctor about the risks and benefits of these and other treatments for mouth sores.

Ask Your Doctor:

  • What can I do if I develop mouth sores?
  • Are they serious?
  • How can I prevent mouth sores?
  • Are there foods I should avoid?
  • Are there foods or drinks that can help?
  • Should I try a medicated mouthwash?


 Print this worksheet 
 and bring them to your next doctor's visit.

A Closer Look: Christine*
Christine
Christine is 39 years old. She is being treated for stage III breast cancer requiring neoadjuvant chemotherapy.
Feeling certain she can get through the treatment without delays or dose reductions, Christine makes checklists of what to do before starting chemo.
She has a dental exam and cleaning.
Christine's doctor advises her to use antibacterial toothpaste and to rinse with saltwater prior to chemo treatments.

*This is a fictional case study based on chemo patient experiences. Your experience is unique. Your doctor and care team will create a plan that will best treat your type of cancer and manage your chemo side effects.

  • The Chemotherapy and Infection Discussion Guide can help you understand your
    chance for infection

    Infection can be a serious result of chemo. Find out the factors that affect your chance of infection. Simply answer a few questions, and then print your results to share with your doctor.

    Use the Chemotherapy and Infection Discussion Guide to find out more.

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