The lining, or mucosa, in your mouth and throat is a very sensitive area of the body. Many chemotherapy drugs can cause this lining to become inflamed. Sores in the mouth and/or throat may form. This is called mucositis. Mouth and throat sores are common and usually occur several days after chemotherapy starts. This can be one of the most uncomfortable and painful side effects of chemotherapy. The sores may make it difficult to talk, eat, drink or swallow.

The mouth sores may also become infected by the germs that live in your mouth. Infections can be difficult to fight during chemotherapy and this may lead to serious problems.

Because it is important to avoid infections, you should do everything you can do to avoid mouth sores or reduce their severity. Good oral hygiene is the most important thing you can do to prevent mouth sores. Visit your dentist before starting chemotherapy, followed by daily brushing and flossing to reduce plaque.

What you can do to prevent mouth or throat sores

• Before beginning chemotherapy, have a dental check-up with scaling, cleaning and repair of cavities.
• Ask your dentist to show you the best way to brush and floss your teeth during chemotherapy.
• During treatment, brush daily and gently with a soft toothbrush.
• Avoid commercial mouthwashes, especially those that contain alcohol.
• Keep your mouth moist. If your mouth is dry, suck on a popsicle or hard candy.

If you do get mouth sores, contact your healthcare team because you may need medical treatment. They can also give you medication to relieve the pain caused by the sores.

If the sores are painful and keep you from eating, try some of the following suggestions.

• Eat soft foods at a lukewarm or cool temperature.
• Avoid tart, salty, acidic or spicy foods.
• Drink lots of fluids. This will help the healing of the sores.
• Use baking soda and water for brushing. This may be less irritating then commercial toothpaste.
• Remove any dentures frequently to give your gums a rest.
• Ask your healthcare team about mouth rinses that may relieve the pain.

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