Oral side effects caused by cancer treatments

Cancer treatments can lead to a number of oral side effects:

Soreness and ulcers in the mouth (stomatitis or oral mucositis) – It is common to have a sore mouth. Small cracks and ulcers can form on any soft tissue in your mouth, causing difficulty in eating, talking and swallowing. These can sometimes bleed and become infected. The sores can be very painful and may worsen over time, but will improve when treatment finishes.
Mouth changes – You might experience mucositis (ulcers) in the mouth or a dry mouth.
Tooth decay – Your teeth may be at increased risk of decay, especially if you have a dry mouth. Oral health care advice before, during and after treatment is important to preserve your teeth and gums.
Mouth infections – The most common is thrush, which usually appears as white patches or a white or yellow coating on the lining of the mouth and tongue. This can cause oral discomfort and bad breath.
Bleeding gums – Your gums may look red, shiny or swollen and they may bleed. Bleeding may occur if your platelet count falls which can happen with chemotherapy. Platelets are the part of the blood that help it to clot.
Taste changes – Cancer treatment may make foods taste different, which can decrease your interest in eating (appetite).
Trouble swallowing and opening your mouth fully – This can be caused by head and neck cancer treatment and severe mucositis.

The type of side effects you experience depends on your treatment. Not everyone will have all of these side effects.

Check your mouth, tongue and teeth regularly during cancer treatment. If you have oral side effects, tell your cancer care team. You may be prescribed pain medication, including antiseptic lotions and sprays that can make you more comfortable. Learn more about ways to manage side effects.

I was constantly told to check my mouth. My husband wanted to help but we were not always sure what to look for. This information would have been a great help to me at the time of my treatment.

Mary, head and neck cancer survivor

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This information was last reviewed in May 2016. View who reviewed this content.

This information was developed in May 2016 and reviewed by: Professor Richard Logan, Oral Pathology and Deputy Head of School, School of Dentistry, Faculty of Health Sciences, University of Adelaide, SA, Dr Sharon Liberali, Director and Consultant, Special Needs Unit, Adelaide Dental Hospital, SA Dental Service, Megan Nutt, Head and Neck Cancer Specialist Nurse, Canberra Region Cancer Centre, Canberra Hospital, ACT, Katherine Garner, Radiation Oncology Dietitian, Northern NSW Cancer Institute, Robyn Burnett, Speech Pathologist, Royal Adelaide Hospital, Mary Mills, Head and Neck Cancer Survivor, Karen Hall, Clinical Nurse, Flinders Medical Centre and 13 11 20 nurse SA.

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