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Mouth sores and ulcers are a common side effect of chemotherapy and radiation therapy. This is known as oral mucositis. The sores can form on any soft tissue in your mouth, making eating, swallowing and talking difficult. This is usually short-term and goes away as you recover from treatment.
Your doctor can give you medicines to reduce the pain when you eat, drink or speak. Some pain relief medicines can be applied directly to the mouth sores to numb them.
Your dietitian can suggest foods to reduce discomfort. You may need to choose softer foods and nourishing fluids. If you are unable to eat and drink enough to meet your nutritional needs, you may need a feeding tube to support you during recovery.
For more on this, see Mouth health and cancer treatment.
Radiation therapy to the head or neck area can cause dry mouth (xerostomia), which is often long-lasting. This can make chewing, swallowing and talking difficult. A dry mouth can also make it harder to keep your teeth and mouth clean, which can increase the risk of damage to your teeth. See the table below for some ways to manage a dry mouth.
Mouth sores and ulcers
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A/Prof David Wiesenfeld, Oral and Maxillofacial Surgeon, Director, Head and Neck Tumour Stream, The Victorian Comprehensive Cancer Centre at Melbourne Health, VIC; Alan Bradbury, Consumer; Dr Ben Britton, Senior Clinical and Health Psychologist, John Hunter Hospital, NSW; Dr Madhavi Chilkuri, Radiation Oncologist, Townsville Cancer Centre, The Townsville Hospital, QLD; Jedda Clune, Senior Dietitian (Head and Neck Cancer), Sir Charles Gairdner Hospital, WA; Dr Fiona Day, Staff Specialist, Medical Oncology, Calvary Mater Newcastle, and Conjoint Senior Lecturer, The University of Newcastle, NSW; Dr Ben Dixon, ENT, Head and Neck Surgeon, Peter MacCallum Cancer Centre and St Vincent’s Hospital Melbourne, VIC; Emma Hair, Senior Social Worker, St George Hospital, NSW; Rosemerry Hodgkin, 13 11 20 Consultant, Cancer Council WA; Kara Hutchinson, Head and Neck Cancer Nurse Coordinator, St Vincent’s Hospital Melbourne, VIC; A/Prof Julia Maclean, Speech Pathologist, St George Hospital, NSW; Prof Jane Ussher, Chair, Women’s Health Psychology, Translational Health Research Institute (THRI), School of Medicine, Western Sydney University, NSW; Andrea Wong, Physiotherapist, St Vincent’s Hospital Melbourne, VIC. We also thank the health professionals, consumers and editorial teams who have worked on previous editions of this title.
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