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Mouth problems with cancer

Mouth care and cancer

Looking after your mouth is important when you have cancer. You can get useful tips on how to cope with common mouth problems.

It's important to keep your mouth very clean and moist:

  • during cancer treatment

  • if you're not eating and drinking normally

  • if you're at risk of infections

General mouth care

  • Let your doctor or specialist nurse know if your mouth is getting sore - they can prescribe medicines to help.

  • Clean your mouth and teeth gently every morning, evening and after each meal.

  • Use a soft bristled or child's toothbrush.

  • Use alcohol free mouthwash instead if your toothpaste stings or if brushing your teeth makes you feel sick.

  • You can use dental floss gently every day (if your doctor agrees) but be careful not to harm your gums.

  • Your doctor or specialist nurse can prescribe mouthwashes containing local anaesthetic if your mouth is very sore.

  • Clean your dentures every morning, evening and after each meal.

  • Use lip balm to keep your lips moist.

  • Moisten your mouth at least every 2 hours with mouthwash or a foam if you're not eating or drinking normally.

  • Salt water or bicarbonate of soda rinses can help to keep your mouth clean.

Support from your doctor, nurse or dentist

When you have radiotherapy to your mouth, you may need to see your dentist for a check up. This is usually at least 2 weeks before treatment begins.

Your dentist will check for any tooth decay or gum problems. They’ll treat these before you begin your radiotherapy.

Your doctor or specialist nurse might give you one or more alcohol free mouthwashes to use every 4 hours while you're having treatment. This is to help stop infection.

You might have anti fungal lozenges, drops or mouthwashes too. It’s important that you try to remember to use these as prescribed.

Your doctor might give you a mouthwash that contains local anaesthetic if you have a very sore mouth. You use it several times a day. Ask your doctor about this if you think it might help you.

You can also have painkillers. Some people have morphine drips (infusions) because their mouths are so sore. So do tell your doctor or nurse if your mouth is painful.

Flossing

Dentists recommend flossing to keep your mouth fresh and clean. But it can damage the gums.

This matters because blood cells called platelets are important for blood clotting. But people having chemotherapy can have a low platelet count. This is common with the high dose courses of chemotherapy for leukaemia or lymphoma.

Your doctor might not want you to use dental floss if you have a low platelet count because it can make your gums bleed. Check with your doctor or specialist nurse first.

There are alternatives, such as inter dental toothpicks or gum stimulators (rubber tips). But be careful with these too. Sticking anything in between your teeth can cause gum damage. Infection can get in if your gums are bleeding.

Tips for coping with problems

Last reviewed: 23 Apr 2024

Next review due: 23 Apr 2027

Resources and support

There are lots of organisations, support groups and helpful books to help you understand mouth problems and get the treatment and support you need.

Mouth problems and cancer treatment

There are different ways you can cope with mouth problems caused by cancer and its treatments. These include mouthwashes, painkillers and changes to your diet and mouth care routine.

Managing diet problems and cancer

Medicines, soft diets, adding calories to your diet or tube feeding are some of the ways to manage diet problems.

Head and neck radiotherapy side effects

Radiotherapy to the head and neck can cause problems with your mouth or teeth, such as a sore or dry mouth, tooth decay or thrush. Find out about ways to manage these side effects.

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