Managing Mouth Sores

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The following information is based on the general experiences of many prostate cancer patients. Your experience may be different. If you have any questions about what prostate cancer treatment services are covered by your health insurance, please contact your health care provider or health insurance provider. This education material was made possible by a Grant from the California Department of Justice, Antitrust Law Section, from litigation settlement funds to benefit Californians diagnosed with cancer or their families.

What Will I Learn By Reading This?

When you have chemotherapy (key-mo-ther-a-pee) to control your prostate cancer, you may have side effects or unwanted changes in your body. Side effects are different from person to person, and may be different from one treatment to the next. Some people have no or very mild side effects. The good news is that there are ways to deal with most of the side effects. In this booklet you will learn:

  • What a mouth sore is
  • Why chemotherapy causes mouth sores
  • Things you can do to manage your mouth sores
  • When to call your doctor

It is important for you to learn how to manage the side effects you may have from chemotherapy so that you can keep doing as many of your normal activities as possible.

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What Are Mouth Sores?

Mouth sores are like little cuts or ulcers in your mouth. The sores may be very red or they may have small white patches in the middle. The sores can be painful. The sores can also make it hard for you to eat, talk, swallow and breathe. Sores can appear on any of the soft tissues of your lips or your mouth, including your gums, your tongue or the roof and floor of your mouth.

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Why Does Chemotherapy Cause Mouth Sores?

The powerful anticancer medicines you take can affect the healthy cells in your body, including the cells that line the inside of your mouth (mucus membranes). Damage to the healthy cells in your mouth makes it difficult for your mouth to heal itself and to fight off bacteria, leading to mouth sores. When this happens it is called mucositis (mu-ko-site-is) or stomatitis (stow-ma-tie-tis).

Mouth sores usually appear a few days after your treatment starts and go away 10 to 14 days after your treatment ends. Your mouth sores may start as a mild pain or burning in your mouth. Your mouth sores will be at their worst around the seventh day after your chemotherapy treatment. Whether you get mouth sores or not depends on:

  • The kind of chemotherapy medicine you are given
  • How much chemotherapy medicine you get
  • How you take your chemotherapy medicine

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How May My Mouth Sores Be Treated?

Right now, there is no medicine that can prevent mouth sores caused by your chemotherapy treatment. When caring for your mouth sores, the goal is to:

  • Shorten the amount of time you have mouth sores
  • Keep your mouth sores from getting so bad that you have trouble eating, talking, and drinking
  • Give you relief from any pain that the mouth sores cause
  • Keep you from getting an infection (when germs enter your body causing you to have a fever or pain, redness, and swelling in one part of your body)

If your mouth is sensitive or you see any sores forming, talk to your doctor. Your doctor may give you medicine to protect the inside of your mouth and to reduce the amount of pain your mouth sores cause.

Though mouth sores can be upsetting, remember that they are temporary and any pain you have can be treated. Don’t worry about giving mouth sores to someone. You cannot give mouth sores to anyone if you kiss them or if you share a glass, fork, spoon, knife, or towel.

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What Can I Do To Manage My Mouth Sores?

Just as every cancer patient’s treatment is different, the way each person responds
to his treatment is also different. While one person may get mouth sores, another
may not. However, there are things you can do to help deal with this treatment side

Keep your mouth moist.

  • Drink 8 eight-ounce glasses of water each day.
  • Suck on ice chips.
  • Chew sugarless gum or suck on sugar-free hard candy.

Clean your mouth, tongue, and gums.

  • Brush your teeth, gums, and tongue with an extra-soft toothbrush after every meal and at bedtime. If brushing hurts, soften the bristles in warm water.
  • Use fluoride toothpaste.
  • Don't use mouthwashes with alcohol in them. Mouthwashes with alcohol can burn your mouth.
  • Floss your teeth gently every day. If your gums bleed and hurt, stay away from the areas that are bleeding or sore, but keep flossing your other teeth.
  • Rinse your mouth several times a day with a solution of 1/4 teaspoon baking soda and 1/8 teaspoon salt in one cup of warm water. You may also use a mixture of 1/2 cup of hydrogen peroxide mixed with 1/2 cup of water. Then, rinse with plain water.

If your mouth is sore, watch what you eat and drink.

  • Choose foods that are good for you and easy to chew and swallow.
  • Stay away from caffeine and alcoholic drinks.
  • Take small bites of food, chew slowly, and sip liquids with your meals.
  • Eat soft, moist foods such as cooked cereals, milkshakes, mashed potatoes, and scrambled eggs.
  • Stay away from acidic foods such as oranges, lemons, limes and tomatoes, salty foods such as pickles and vinegary foods, and spicy foods such as chilies.
  • Stay away from hard, dry sticky foods like crackers, potato chips, and peanut butter. Eat soft, moist foods like custard, gravies, stewed foods, mashed potatoes, and soft cooked beans.
  • If you have trouble swallowing, soften your food with gravy, sauces, broth, yogurt, or other liquids.
  • If your mouth is tender, eat foods that are cold or at room temperature because hot or warm foods can bother your mouth.

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If your lips are dry and sore.

  • Use lip balm like Vaseline if your lips are dry. And if you are bothered by mouth dryness, ask your doctor about medicines that may help.

Seeing a dentist.

  • Talk to your doctor about seeing a dentist before you start chemotherapy.
  • Check with your doctor before you have your teeth cleaned or any dental work done by a dentist.

If you have mouth sores.

  • Ask you doctor or health care team about medicines for your mouth sores.
  • Don't use over-the-counter (medicines you buy without a prescription from your doctor) medicines unless you check with your doctor.
  • If pain is gets in the way of your eating and drinking, be sure to tell you doctor or health care team.
  • If it is difficult or painful to swallow, tell your doctor or health care team.

Plan For Managing Your Mouth Sores

  • What foods can you eat that will make your mouth sores better?
  • What foods should you stay away from if you have mouth sores?
  • What can you do to keep your mouth clean and healthy during your chemotherapy treatment?
  • How do you get in touch with your doctor or health care team if you need help?

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When Should I Call My Doctor?

You should call your doctor if you have:

  • A fever higher than 100° F or 38° C
  • Sores in your mouth or on your lips that keep you from eating, drinking or sleeping
  • Pain or any sign of infection
  • Sores in your mouth or on your lips that get worse even if you are doing everything your doctor or healthcare teams has told you to do to make them better

If you have any of these signs talk to your doctor or health care team. There are medicines and treatments that can help you feel better. It is important that you talk to your doctor or health care team about any side effects you may have during or after your treatment. Your health care team can help treat these problems.

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What Have I Learned By Reading This?

You learned about:

  • What a mouth sore is
  • Why chemotherapy can cause mouth sores
  • How to treat your mouth sores
  • Things you can do to help manage your mouth sores
  • When to call your doctor

If you have any questions, please talk to your doctor or health care team. It is important that you understand what is going on with your prostate cancer treatment. This knowledge will help you take better care of yourself and feel more in control so that you can get the most from your treatment.

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Key Words

  • Anticancer: medicines used in the treatment of cancer.
  • Chemotherapy (key-mo-ther-a-pee): a prostate cancer treatment, which treats your whole body with powerful anticancer medicines to kill many of your prostate cancer cells.
  • Germ: tiny living organisms that can’t be seen with the human eye that can make you sick.
  • Infection: when germs enter your body causing you to have a fever or pain, redness, and swelling in one part of your body.
  • Mouth sores: small cuts or ulcers that appear on your lips or mouth during your chemotherapy treatment.
  • Mucositis (mu-ko-site-is): mouth sores caused by chemotherapy treatment.
  • Mucus membranes: the cells that line the inside of your mouth.
  • Over-the-counter : medicines you buy without a prescription from your doctor.
  • Side effects: unwanted changes in your body caused by your prostate cancer treatment.
  • Stomatitis (stow-ma-tie-tis): mouth sores caused by chemotherapy treatment

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