Mouth sores
Some chemotherapy drugs can damage healthy cells in the mouth and cause mouth sores, such as ulcers or infections.
Chemotherapy treatment may also reduce the amount of saliva (spit) in your mouth, make your saliva thick or sticky, or make your mouth dry. This is called xerostomia or dry mouth. If you notice any sores, ulcers or thickened saliva, or if you find it difficult to swallow, tell your doctor.
For more on this, see Mouth health and cancer treatment and Taste and smell changes.
Looking after your mouth
- Discuss any dental issues with your oncologist or haematologist before seeing the dentist. If you need to have any dental work, tell your dentist you’re having chemotherapy.
- Use a soft toothbrush to clean your teeth twice a day.
- Rinse your mouth often – when you wake up, after you eat or drink, and at bedtime. Ask your doctor or nurse what type of alcohol-free mouthwash to use. They may give you a recipe for a homemade mouthwash. Talk to your doctor or nurse about medicines to relieve pain and help with healing.
- Sip fluids, especially water, and eat moist foods such as casseroles or soups if you have a dry mouth.
- Soothe tender gums or mouth with plain yoghurt.
- Try sucking on ice during chemotherapy sessions. This may help to prevent mouth ulcers.
- Blend foods to make them easier to eat. Try smoothies made of fruit and yoghurt.
- Avoid smoking and alcoholic drinks, as well as very hot foods and spicy, acidic or coarse foods (e.g. nuts or grains). These can all make mouth sores worse.
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