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Mouth care routine


During chemotherapy, it is important to take good care of your child’s mouth. This is because many types of chemotherapy can cause mouth problems, such as painful sores. Chemotherapy is the medical term for medicines that kill cancer cells or stop them from growing. A regular mouth care routine is important when your child gets chemotherapy.

What is a mouth care routine?

A mouth care routine is the things you and your child do to take care of his mouth. It can include:

  • Brushing teeth,
  • Rinsing the mouth,
  • Using lip balm, and
  • Getting “cold therapy” to help prevent mouth sores.

Why is preventing mouth sores important?

Mouth sores are a common side effect of chemotherapy. Not everyone who has chemotherapy will get mouth sores. It depends on the chemotherapy medicines and doses. But many people do get mouth sores. The sores can cause the following problems.

  • Pain – From mild to severe (very bad). Your child might need a strong pain medicine for severe pain.
  • Problems eating, drinking, and swallowing – This can lead to poor nutrition. If your child cannot eat or drink because of mouth sores, doctors might need to give fluids or nutrition through a thin tube that goes into a vein. This tube is called an "IV."
  • Higher risk of getting an infection.
  • More healing time – Waiting for mouth sores to heal can make your child stay in the hospital longer. It might also slow down chemotherapy.

The mouth care routine

Brushing teeth

  • Have your child brush his teeth 15 minutes after eating and 15 minutes after mouth care. Also, have your child brush after eating sweets or sugary foods. Teeth should always be brushed at least 2 times a day.
  • Use a soft toothbrush. Let it dry completely after each use.
  • If your child cannot brush his teeth, clean them with a piece of moist gauze wrapped around one (1) finger. You can also use a small sponge or a foam toothbrush. The St. Jude staff can help you get these items.
  • If your child swallows toothpaste, clean his teeth with plain water.
  • Use a new toothbrush every 2 months or sooner if the bristles wear down.
  • Use a new toothbrush every day if:
    • Your child had a bone marrow (stem cell) transplant,
    • Your child has an absolute neutrophil count (ANC) of less than 500, or
    • Your child has an infection or bleeding in his mouth.
  • If your child’s ANC is greater than 500, soak the toothbrush in chlorhexidine gluconate mouthwash for 15 minutes every day. This mouthwash is also called CHG or Peridex®. If your child is not staying in the hospital, you may use Listerine® mouthwash if you cannot get CHG or Peridex.

Rinsing your child’s mouth

Rinse your child’s mouth with 5 to 10 milliliters (ml) of a mouth rinse at least 3 times each day. Mouth rinses include Biotene®, alkaline saline, and Cepacol®.

Using lip balm

Put a lip balm, ointment, or cream with lanolin on your child’s lips at least twice a day. Also, use lip balm whenever your child’s lips are dry. If your child is old enough, you can teach him to do this.

Foods to eat during treatment

The best foods for your child are soft foods like applesauce, pudding, ice cream, and mac ‘n’ cheese. Your child should also drink plenty of water. The nurse can tell you if other fluids are all right to drink. St. Jude dietitians created “Do You Know… Sore Mouth Diet.” It has ideas for the best foods and drinks for your child’s sore mouth. Ask a dietitian or your nurse for a copy.

Your child should not eat salty or spicy foods or dry, crunchy foods that could scrape his mouth. The nurse or the dietitian can tell you which foods might irritate the mouth.

Checking for mouth sores

The St. Jude staff will check your child’s mouth for sores every day. Please tell the staff right away if your child has any of the signs below.

  • Blisters, sores, or white patches in the mouth – Or blisters on the lips
  • Pain on the lips or in the mouth – Including a sore throat
  • Upset stomach, cramps, or diarrhea
  • Bleeding from the gums
  • Trouble swallowing, eating, or drinking
  • Extra fluid in the mouth or throat
  • A fever of 100.4 degrees F (38 degrees C) or higher

Cold therapy

Cold therapy is using ice chips or other cold materials to cool the mouth. Your child can do this during certain types of chemotherapy. The medical term for this type of cold therapy is “oral cryotherapy” (say KRAHY-oh-ther-uh-pee).

Research shows that cold therapy can prevent mouth sores. It can also make them less severe or last a shorter time.

How to do cold therapy

Your child should chew on ice chips or other cold item during chemotherapy. Start a few minutes before the chemotherapy starts. Keep doing cold therapy for up to 60 minutes. The staff will ask which cold items are best for your child. These can include ice, popsicles, cold water, ice cream, slushy drinks, or a cold teething ring.

Your child should move the cold items around the whole mouth to keep it cold. When the item melts or gets warm, your child needs more.

Is cold therapy safe?

Yes. Research shows cold therapy is safe. There are only a few minor side effects. These include headaches, chills, numbness, changes in how things taste, and tooth pain.

If your child gets mouth sores

If your child gets mouth sores, the nurse may give your child a mouthwash, gel, or spray to make the sores hurt less. Your child might also take medicine to help the pain or stop an infection.

Playing or doing arts and crafts or homework can help your child stop thinking about mouth sores. This can help him feel less pain.

Mouth sores sometimes bleed. This might be a little, or more severe. If your child’s mouth sores bleed a lot, St. Jude staff might give him some extra blood to replace what he loses. If your child needs this treatment, the doctor or nurse will tell you.


If you have questions or concerns about your child’s mouth care routine, please talk to your child’s doctor or nurse.

This document is not intended to take the place of the care and attention of your personal physician or other professional medical services. Our aim is to promote active participation in your care and treatment by providing information and education. Questions about individual health concerns or specific treatment options should be discussed with your physician.  


St. Jude complies with health care-related federal civil rights laws and does not discriminate on the basis of race, color, national origin, age, disability, or sex.

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