Mouth, Gum & Throat Problems

During cancer treatment, some patients may get painful sores in their mouth and throat. Other problems can also affect the mouth and throat and cause unwanted symptoms.

Oral hygiene is important if you get chemotherapy, a stem cell transplant, or radiation for head and neck cancer.

Causes of Mouth, Gum, and Throat Problems

Radiation therapy to the head and neck may make it hard to chew and swallow safely. Some types of chemotherapy and immunotherapy can also harm your mouth, throat, and lips. Drugs used to treat cancer and certain bone problems may also cause oral problems.
Mouth and throat problems may include:

  • Changes in taste (dysgeusia) or smell
  • Dry mouth (xerostomia)
  • Mouth sores
  • Infection
  • Pain or swelling in your mouth (oral mucositis)
  • Sensitivity to hot or cold foods
  • Swallowing problems (dysphagia)
  • Tooth decay (cavities)

Tips for Keeping Your Mouth Healthy

  • Learn the signs of mouth and throat problems.
  • Talk to your doctor. Prepare for your visit by making a list of questions to ask. Consider adding these questions to your list:
    • When might these problems start to occur? How long might they last?
    • What steps can I take to feel better?
    • What medicines can help?
    • What symptoms or problems should I call the doctor about?
    • What pain medicine and/or mouthwashes could help me?
    • Would you recommend a registered dietitian I could see to learn about good food choices?
    • For people receiving radiation therapy to the head and neck: Should I take supplements such as zinc to help my sense of taste come back after treatment?
  • Get a dental check-up before starting treatment. Tell the dentist about your cancer treatment and try to get any dental work completed before starting treatment.
  • For a sore mouth or throat:
    • Choose foods that are soft, wet, and easy to swallow.
    • Soften dry foods with gravy, sauce, or other liquids.
    • Use a blender to make milkshakes or blend your food to make it easier to swallow.
    • Ask about pain medicine, such as lozenges or sprays that numb your mouth and make eating less painful.
    • Avoid foods and drinks that can irritate your mouth; foods that are crunchy, salty, spicy, or sugary; and alcoholic drinks.
    • Don’t smoke or use tobacco products.
  • For a dry mouth:
    • Drink or rinse your mouth with liquids because a dry mouth can increase the risk of tooth decay and mouth infections.
    • Keep water handy and sip it often to keep your mouth wet.
    • Suck on ice chips or sugar-free hard candy, have frozen desserts, or chew sugar-free gum.
    • Ask about medicines such as saliva substitutes that can coat, protect, and moisten your mouth and throat.


  • Ask your nurse or doctor to recommend a mouth rinse for you.
  • Gently brush your teeth, gums, and tongue after each meal and before going to bed at night. Use a very soft toothbrush or cotton swabs.
  • Find tips to address changes to your sense of taste.
  • Listen to this audio recording on managing mouth and throat pain during radiation therapy.

Get Support

For more detailed information on support options, visit Get Support.

Talk to Your Health Care Team

Your health care team needs to know how you’re doing. Be sure to tell them about any changes you notice.

Talk to Family and Friends

Your loved ones want to support you. They can help with activities like housework, running errands, and getting to appointments. Be as specific as possible about the kind of help you need.

Find Peer Support

Talk About Your Concerns

Peer groups offer a welcoming environment to share your feelings and experiences with people who are going through the same things. Use the American Cancer Society’s Resource Search to find a peer group in your area or call the American Cancer Society at 1-800-227-2345 for personalized assistance.

Visit the Cancer Survivors Network Online

The Cancer Survivors Network is an online community with more than 40 discussion boards where cancer survivors share their cancer-related experiences, support one another, and exchange practical tips.

NCI Cancer Information Service


Speak to a National Cancer Institute health information specialist by calling 1-800-4-Cancer.


The National Cancer Institute offers live, online assistance through its LiveHelp service.

ACS National Cancer Information Center

Get Tips

Get information and tips from a cancer information specialist at the American Cancer Society by calling 1-800-227-2345. Lines are open 24 hours a day, 7 days a week.


The American Cancer Society offers live, online assistance 24 hours a day, 7 days a week. Select the Live Chat option from any page on

Learn More About Mouth, Gum, and Throat Problems

The National Cancer Institute and American Cancer Society have additional resources to help you manage mouth and throat problems.