Mouth Sores due to Chemotherapy


Other terms: mucositis, stomatitis, esophagitis, sore mouth

What Is Mucositis (Mouth Sores)?

Mucositis is an inflammatory reaction of the mucous lining of the upper gastrointestinal tract from mouth to stomach (mouth, lips, throat) and surrounding soft tissues.

  • Stomatitis refers to inflammation in the mouth.
  • Esophagitis refers to inflammation of esophagus.
  • Mucositis refers to all mucous linings.

This response is due to certain chemotherapeutic drugs, biologic response modifiers, radiation therapy, and/or surgery. This reaction may progress to painful ulcers and infection, interfering with eating, talking, taste, chewing or swallowing and often lasting a few days.

Mucositis is a self-limiting condition, currently there is no agent available to consistently prevent or treat this condition. The goal is to decrease the severity and duration of mucositis and to provide relief of discomfort, and prevent or treat infection until recovery.

Things You Can Do To Manage Oral Problems:

  • Keep mouth and lips moist:
  • Rinse mouth with water frequently (every 2 hrs while awake & when awake during the night). May add salt or baking soda (1/2 to 1 teaspoon in 8 ounces of water).
  • Use saliva substitute (commercially available) if needed.
  • Apply lip moisturizer often (i.e. chap stick).Suck on hard candies.
  • Keep mouth & teeth clean.
  • Use soft-bristle toothbrush (can soften even more by placing brush in very warm water), cotton swabs, mouth swabs (popsicle stick covered with gauze) to clean teeth after each meal and at bedtime.
  • Clean dentures and/or bridge after eating. Leave out dentures if experiencing any discomfort.
  • Floss gently with unwaxed floss (if platelet count adequate).
  • May use Water-Pik.
  • Avoid:
  • Mouthwash containing alcohol.
  • Lemon glycerin swabs.
  • Treat the discomfort/pain.
  • Use topical or local agents such as Orajel, or Zilactin-B apply generously.
  • Combination mouth wash can be made (ingredients may require prescription).
  • Use equal parts: xylocaine viscous solution, Zovirax® (alcohol-free), and Maalox®, or Mylanta®.
  • Take 2 teaspoons every 2-4 hours as needed (swish around mouth and spit out).
  • May be advised by healthcare provider to swallow if experiencing discomfort while swallowing.
  • For severe pain: oral or intravenous pain medication* may be required in addition to topical medication (* prescribed by healthcare provider).
  • Enhance healing:
  • Apply Orabase®, Ulcerase®, etc. to irritated areas in mouth or on lips.
  • Apply Vitamin E (puncture cap 400IU and squeeze onto swab. Gently place swab on open area(s).
  • Take an antacid 1/2-1 ounce every 3-4 hours as needed to decrease burning sensation.
  • Maintain good nutrition focusing on high protein and high calorie foods which are soft and/or semi liquid (i.e. scrambled eggs, puddings, blenderized or pureed foods). May use liquid supplements (i.e Carnation Instant Breakfast®, Ensure®, Boost®, etc.).
  • Avoid:
  • Hot, spicy, coarse or rough textured foods.
  • Very hot or cold beverages and foods.
  • Citric juices or foods containing citric acid (tomatoes, oranges, lemon, etc.).
  • Alcoholic beverages or tobacco products.
  • Liquid medication containing alcohol (i.e. some cough medicine) if not essential.

Drugs That May Be Prescribed by Your Doctor:

To treat or prevent infection the following may be used:

  • Antifungals: Such as nystatin,clotrimizole, fluconozole
  • Antibacterials: Mouthwash antiseptic, rinses are the basis of the oral decontamination regimen.
  • Chlorhexidine gluconate (Peridex®, PerioGard®).
  • Brush and floss teeth, and completely rinse toothpaste from mouth, before using rinse.
  • Antivirals: Such as acyclovir (Zovirax®) or famciclovir (Famvir®)

To protect Gastrointestinal (GI) tract from irritants:

  • Gastrointestinal agents: Sucralfate (Carafate®), comes in a liquid suspension form, protects the lining of the mouth to the stomach from irritants.
  • Analgesics for pain control

When to Contact Your Doctor or Health Care Provider:

  • Temperature greater than 100.5 F (38 C).
  • Sores or ulcers in mouth or on lips that interfere with eating, drinking or sleeping.
  • Pain or any sign of infection (i.e. tongue heavily coated).
  • Symptoms increasing in severity despite above recommendations.

Always inform your health care provider if you experience any unusual symptoms.

Note: We strongly encourage you to talk with your health care professional about your specific medical condition and treatments. The information contained in this website is meant to be helpful and educational, but is not a substitute for medical advice.

Related Side Effects

Sore Mouth has related side effects:

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