- Cancer Information
- Cancer treatment
- Managing chemotherapy side effects
- Mouth sores
Some chemotherapy drugs can cause mouth sores, such as ulcers, or infections. This is more likely if you have had or are having radiation therapy to the head, neck or chest area, high-dose chemotherapy or a stem cell transplant, or if you have dental or gum problems or need a course of antibiotics.
If you notice any sores, ulcers or thickened saliva, or if you find it difficult to swallow, tell your doctor.
Looking after your mouth
- Discuss any dental issues with your oncologist or haematologist before seeing the dentist. If you need any dental work, tell your dentist you’re having chemotherapy.
- Use a soft toothbrush to clean your teeth twice a day.
- Rinse your mouth four times a day with 1/4 tsp bicarbonate of soda and 1/4 tsp salt dissolved in a cup of warm water. Avoid mouthwashes with alcohol.
- Sip fluids, especially water, and eat moist foods such as casseroles or soups if you have a dry mouth. Moisten foods with gravy or sauce.
- Soothe tender gums or mouth with plain yoghurt.
- Sucking on ice during chemotherapy sessions 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.
For more on this, see Mouth health and cancer treatment.
Download a PDF booklet on this topic.
Clinical A/Prof Rosemary Harrup, Director, Cancer and Blood Services, Royal Hobart Hospital, TAS; Katie Benton, Advanced Dietitian, Cancer Care, Sunshine Coast Hospital and Queensland Health, QLD; Gillian Blanchard, Oncology Nurse Practitioner, Calvary Mater Newcastle, NSW; Stacey Burton, Consumer; Dr Fiona Day, Staff Specialist, Medical Oncology, Calvary Mater Newcastle, and Conjoint Senior Lecturer, The University of Newcastle, NSW; Andrew Greig, Consumer; Steve Higgs, 13 11 20 Consultant, Cancer Council Victoria; Prof Desmond Yip, Clinical Director, Department of Medical Oncology, The Canberra Hospital, ACT.
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