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Mouth Care for the Cancer Patient


Mouth care is important because it prevents and treats common side effects of chemotherapy and radiation therapy. A dry mouth, an altered sense of taste, and mouth sores can make it hard for you to eat, swallow, or talk. Mouth sores could lead to a life-threatening infection. Mouth sores could also delay your treatment or make it less effective. Mouth care can decrease pain and help keep your treatment on schedule. It can also improve your quality of life and ability to eat.


Return to the emergency department if:

  • Your heart is racing.
  • You have trouble breathing.
  • You cannot eat or drink.

Contact your healthcare provider or oncologist if:

  • You have a fever or chills.
  • You notice changes in your mouth, such as bleeding, white patches, or a white film on your tongue.
  • Your mouth sores do not improve within 3 weeks after your chemotherapy ends.
  • Your mouth sores do not improve within 6 weeks after your radiation therapy ends.
  • You have questions or concerns about your condition or care.

Follow up with your healthcare provider or oncologist as directed:

Bring a list of any questions you have so you remember to ask them during your visits.

Do not smoke:

Smoking can make mouth sores worse and delay healing after treatment. Smoking also increases your risk for new or returning cancer. Do not use e-cigarettes or smokeless tobacco in place of cigarettes or to help you quit. They still contain nicotine. Ask your healthcare provider for information if you currently smoke and need help quitting.

Brush and floss your teeth safely:

  • Use a soft toothbrush and plain fluoride toothpaste. Do not use tarter control or whitening toothpaste. Let your toothbrush air dry after each use to prevent bacteria growth. Replace your toothbrush often.
  • Gently brush your teeth, gums, and tongue after every meal and before bed. Do this even if you are not eating. There are still bacteria in your mouth that need to be brushed away.
  • Rinse your mouth with water if you cannot brush.
  • Continue to use waxed dental floss if you already floss daily. Ask if it is safe to begin flossing during your treatment.

Rinse your mouth with a baking soda or salt solution:

Rinsing removes bacteria and food, and prevents or treats dry mouth, thick, sticky saliva, and mouth sores.

  • Mix ½ teaspoon baking soda or salt with 8 ounces of warm water to make a solution.
  • Rinse your mouth at least 4 to 6 times a day with the solution you made. You may rinse with plain water instead if it feels better to you.
  • Do not use store-bought mouthwash, because it can irritate your mouth.

Prevent or treat a dry mouth:

  • Drink at least 64 ounces (2 to 3 liters) of water or other liquid each day. Do not drink caffeine or alcohol, because they can irritate and dry your mouth. Milk can soothe your mouth and may also strengthen the enamel on your teeth.
  • Suck on ice chips, frozen juice bars, or popsicles to increase saliva. Chew sugar-free gum or suck on sugar-free hard candy. These may also relieve a bad taste in your mouth.
  • Use unflavored lip balm or a water-based moisturizer on your lips. Do not use petroleum jelly.

Prevent or treat thick, sticky saliva:

  • Elevate the head of your bed to help clear saliva while you sleep.
  • Take a shower in the morning. Steam from the shower may help thin and loosen saliva.
  • Drink water or other liquid throughout the day to help prevent dehydration.

Prevent or treat mouth sores:

  • Soft, blended, moist foods are less likely to bother your mouth. Try puddings, milkshakes, broths, soups, and cooked cereals. Eat food at a lukewarm or cool temperature.
  • Do not eat anything that could burn, sting, or scratch your mouth. Examples are oranges, pineapples, hot peppers, potato chips, toast, and alcohol.
  • Take small bites, chew slowly, and sip water while you eat. Rinse your mouth with water after meals.

Mouth care if you wear dentures:

It is still important to clean your gums and mouth if you wear dentures. If your dentures do not fit well, you may not want to wear them during chemotherapy treatment. Be extra careful when you put in or remove dentures. Try to prevent any injuries to your gums that could lead to sores or infection. Soak your dentures in denture solution at night to keep them free from bacteria.

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The above information is an educational aid only. It is not intended as medical advice for individual conditions or treatments. Talk to your doctor, nurse or pharmacist before following any medical regimen to see if it is safe and effective for you.

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.