Sore Mouth and Throat Care During Cancer Treatment

During your cancer treatment, your mouth or throat may feel very dry, sore, or raw. This is a side effect of some chemotherapy drugs and radiation therapy treatments.

Caring for your mouth and throat

The guidelines below will help you prevent or care for a sore mouth and throat:

  • Rinse your mouth with a mixture of 1/2 teaspoon of salt and 8 ounces of water or 1/2 teaspoon of baking soda (sodium bicarbonate) and 8 ounces of water. Your nurse will tell you how often to rinse your mouth. Always rinse after every meal and at bed time. For severe mouth sores, you may be told to rinse every 1 to 2 hours during the day and 1 or more times during the night.
  • If you buy mouth wash at the store, read the label. Avoid mouth washes that contain alcohol, which may cause dryness and may sting.
  • If your mouth or throat is dry, try drinking several glasses of water and other fluids during the day. Carry a water bottle when you travel away from home. Try sucking on sugarless hard candy or chewing sugarless gum. Ask your nurse or doctor about artificial saliva to moisten your mouth.
  • Try drinking through a straw. This helps liquids to bypass sores and other tender areas of your mouth.
  • Keep your lips moist. If your lips have no open areas, you can use a moisturizer that has an oil base. Some examples are lip moisturizers (such as ChapStick® and Blistex®) and petroleum jelly (such as Vaseline®). If your lips have open areas, use only moisturizers that are water soluble (such as K-Y Jelly® or Surgilube®).
  • Continue to clean your teeth even when your mouth is sore. If you cannot use a tooth brush, buy disposable sponge swabs, (such as Toothette® brand). Use the swabs to gently massage your gums, tongue, and soft tissue.
  • Avoid flossing if it makes your gums hurt or bleed or if your platelet count is low.
  • Do not wear dentures or dental plates that do not fit well. Have your dentist adjust or repair them. Do not wear your dentures or dental plates while you sleep. To clean your dentures and dental plates, use denture cleaners that bubble (are effervescent). Rinse the dentures and dental plates well before you wear them.
  • Do not smoke cigarettes, cigars, or pipes. Do not chew tobacco. Do not drink alcohol. All of these will irritate a sore or tender mouth and throat.
  • See your dentist for regular check-ups. Tell your dentist about your cancer treatment. Give your dentist the name and phone number of your oncologist. Before you have any dental work done, it is very important that you discuss it with your oncologist. This includes cleaning, fillings, pulling of teeth, insertion of dental implants, and special gum treatments.
  • Your doctor may prescribe medicine to help numb your mouth and throat. These medicines come as lozenges, sprays, or liquids.
  • Your doctor may prescribe medicine for pain. Take the medicine 1 to 2 hours before meals. If your mouth has constant pain, take your pain medicine at regular times spaced evenly around the clock. Always take it, for example, every 4 to 6 hours, or as ordered by your doctor. If your pain is not relieved, call your doctor or nurse.
  • If you get an infection in your mouth or throat, you may need to take antibiotics. These antibiotics come in different forms. Some are liquids swished in the mouth and throat, and others are applied directly to the mouth and throat. Some are pills taken by mouth. Use these medicines exactly as prescribed.
  • If you have bleeding, apply pressure with a piece of gauze dipped in ice water. Rinsing your mouth and throat with ice water also may help to stop the bleeding.

Getting good nutrition

Good nutrition is very important during your cancer treatment. Eating a healthy diet that is high in protein will help prevent and fight infection. A healthy diet will help your mouth and throat to heal. You will have more energy.

Soft, Bland Diet

Foods to choose

When you have a sore mouth or throat, eat foods that are soft, have a bland taste, and are cold or room temperature. Choose these foods and drinks:
  • Beverages: milk, instant breakfast drinks, nutrition supplement drinks, milk shakes, smoothies, store-bought eggnog, warm caffeine-free tea with sugar, apple juice, apricot nectar, sports drinks
  • Soups: creamed soups
  • Cheese: cottage cheese; any cheese sprinkled over eggs, vegetables, or meat; macaroni and cheese
  • eggs: cooked only
  • Meats and fish: cooked chicken, turkey, beef, pork, or fish that is soft and moist. Add broth, soup, sauces, or gravy to make them moist. If you have trouble chewing, try meat that is ground or pureed.
  • Fruits: bananas, peaches, pears, apples, apple sauce. You may soften or puree any fruit in a blender. You may freeze fruits such as grapes, banana pieces, melon balls, peach slices, or mandarin orange slices.
  • Vegetables: cooked carrots, peas, string beans, broccoli crowns, spinach, and other cooked vegetables that are soft. Add sauces, margarine, or butter to make them moist.
  • Other: cooked cereal, moist casseroles, mashed potatoes, pasta, noodles
  • Desserts: pudding, frozen pops (such as Popsicles®), custard, yogurt, ice cream, gelatin


Foods to avoid

Certain foods and drinks may burn or scratch your mouth when it is sore or tender. To help prevent this problem, do not eat or drink anything while it is hot. Serve all food and drinks cold or lukewarm. Avoid these foods and drinks:


  • Tomatoes; citrus fruits and juices, such as orange, grapefruit, lemon, lime
  • Pepper, chili powder, cloves, nutmeg
  • Salsa, hot pepper sauces, horseradish
  • Rough, dry, or coarse foods
  • All alcoholic drinks

Neutropenic Diet

If your white blood cell count gets very low, you may become neutropenic (nu-tro-PEEnik). This means that the immune system has been weakened. When this happens, certain foods could give you an infection. To prevent infection, you have to avoid certain foods. If your doctor tells you to follow a neutropenic diet, ask your nurse for the UPMC patient education sheet Neutropenic Diet.

Nutrition Supplements

If you are not able to eat enough, you will not get the nutrition you need. Tell your doctor, nurse, or dietitian. Ask about nutrition supplements and liquid meal replacements. Ask for samples to try or for suggestions of which ones to buy.

When to call the doctor

Be sure to tell your doctor or nurse if you have any of the following:

  • Increased redness of your mouth or tongue
  • Soreness or burning in your mouth
  • Cold sores on your lips or in your mouth
  • Blisters, ulcers, or white patches in your mouth
  • Bleeding gums
  • Sore throat
  • Trouble swallowing
  • Inability to eat or drink