by EBSCO Medical Review Board

Image for cancer tests If you are undergoing radiation therapy to treat cancer, you and your doctor may have discussed the different problems that may occur due to treatment. For instance, problems in the oral area (teeth, gums, and throat) are common with radiation therapy to nearby areas. While your cancer care team will manage any oral health problems that may occur from treatment, there are also actions you can take.

Understanding the Problem

Cancer occurs when cells in the body divide without control or order. Radiation treats cancer by killing these out-of-control cells. However, since normal cells also divide (but do so in a regulated manner), they too are killed. This can prevent tissues in the oral area from repairing themselves during normal wear and tear.

Cancer treatment can also disturb the balance of good and bad bacteria in the mouth, as well as affect the lining and saliva. This can eventually lead to infection, sores, and tooth decay. Other oral side effects that may occur are:

  • Mucositis—inflammation of mucous membranes in the mouth
  • Esophagitis—inflammation of the esophagus, which is the muscular tube that connects the throat to the stomach
  • Dry mouth
  • Change or loss of taste
  • Pain
  • Gum disease
  • Problems using the mouth or jaw caused by bone loss or noncancerous tumors

Some of these problems, like mouth sores, will go away once treatment stops, but others may last months or years.

Using Coping Strategies

Before Treatment

Think about your overall health before treatment. The healthier you are, the better able your body will be to prevent problems and fight potential side effects. Being healthy includes following a well-balanced diet. Talk with your doctor or dietitian about a diet plan that is right for you.

Also, if you are having radiation therapy to your head or neck, see a dentist 2 weeks beforehand. The dentist will take care of any existing oral health problems you may have to ensure that you are as healthy as possible before treatment.

Self-care Tips

Once treatment begins, your doctor may prescribe medications to treat any problems that occur. In addition to medications, here are other ways to maintain a healthy mouth during treatment:

  • Check your mouth every day to detect problems, such as mouth sores or white patches. Report any problems to your doctor.
  • Keep your mouth moist. You can do this by:
    • Sucking on ice
    • Sipping water or spraying your mouth with water often throughout the day
    • Chewing sugar-free gum or sucking on hard candy
    • Taking medication prescribed by your doctor to increase saliva
  • Brush your teeth, gums, and tongue after eating and before going to bed. Use a soft toothbrush and fluoride toothpaste. Also, floss gently once a day.
  • Do not use mouthwashes that contain alcohol. Instead, mix ¼ teaspoon (1.23 milliliters [mL]) baking soda, 1/8 teaspoon (.62 mL) salt, and 1 cup (237 mL) of warm water. Rinse your mouth with this solution every 1-2 hours.
  • If you wear dentures, soak and brush them every day.
  • Do not use tobacco. This includes cigarettes, cigars, pipes or chewing tobacco.

Eating and Drinking Tips

  • Eat foods that are easy to chew and swallow, like mashed potatoes and scrambled eggs. You can moisten foods with sauce, broth, or gravy.
  • Foods should be warm or room temperature.
  • Take small bites and chew slowly.
  • Sip water while eating.
  • Drink cool beverages.
  • Avoid foods that may harm your mouth, such as:
    • Crunchy foods, like chips
    • Hot foods
    • Spicy foods
    • Sugary foods and drinks
    • Tomatoes, oranges, lemons, and grapefruits
    • Alcohol
  • Sit up straight and bend your head slightly when eating and drinking. Stay upright for at least 30 minutes after eating.

Your doctor or dietitian may suggest foods that are high in calories and protein so that you can maintain a healthy weight during treatment.

Tips for Dealing with Stiffness

You may experience stiffness in your jaw. If so, your doctor may help relieve this with special devices and medications. There are also some exercises that you can do at home, such as the following:

  1. Open and close your mouth as far as you can without feeling pain.
  2. Do 20 at a time, 3 times per day.

Tips for Dealing With Pain

If you experience pain, you and your doctor will work together to find ways to help relieve it. Your doctor may prescribe medications, as well as other therapies like:

  • Applying cold or heat to the painful area
  • Physical therapy
  • Counseling
  • Acupuncture

Talk With Your Doctor

Tell your doctor anytime you:

  • Feel like you are choking
  • Have trouble swallowing
  • Cough when eating or drinking

Undergoing cancer treatment can be stressful and tiring. But proper self-care and support from your cancer care team will help you to cope successfully as you battle the disease.


American Cancer Society 

National Cancer Institute 


BC Cancer Agency 

Canadian Cancer Society 


Oral complications of chemotherapy and head/neck radiation (PDQ). National Cancer Institute website. Available at: Updated December 16, 2016. Accessed June 29, 2017.

Radiation therapy side effects and ways to manage them. National Cancer Institute website. Available at: Accessed June 29, 2017.

Radiation therapy to the head and neck. American Cancer Society website. Available at: Updated February 10, 2017. Accessed June 29, 2017.

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