Side effects of radiation therapy
The side effects vary depending on the area treated, the number of treatments, the type of radiation therapy you have and whether it is combined with chemotherapy.
Side effects often peak in the final week of treatment, or shortly afterwards, then start to ease 2–3 weeks after treatment ends. Some side effects may last longer, be ongoing or appear several months or years later. Learn more about managing side effects. The most common short-term and long-term side effects are listed below.
During or immediately after treatment – fatigue, mouth sores, taste changes, loss of appetite, dry mouth and thick saliva, skin redness and burning in the area treated, breathing difficulties, weight loss.
Ongoing or permanent – dry mouth, thick saliva, difficulties with swallowing and speech, changes in taste, fatigue, muscle stiffness, neck swelling, appetite and weight loss, oral thrush, hoarseness, dental problems, difficulty opening the mouth, hair loss.
Some people find that food and fluid goes into the windpipe instead of the food pipe. This is called aspiration and it can block the airways and cause difficulty breathing. Some people develop an underactive thyroid (hypothyroidism) and may need to take thyroid hormone replacement tablets after radiation therapy.
For more on this, see Radiation therapy.
Radiation therapy to the head and neck can damage blood vessels, causing bone in the lower jaw to die. This is called osteoradionecrosis (ORN). ORN affects around 5–7% of people who have radiation therapy to the head and neck. It can occur months or years after treatment. Having any necessary dental work before treatment starts reduces the risk of ORN. Treatment may include antibiotics, other medicines or surgery. To help the bone heal, you may also have hyperbaric oxygen treatment (breathing in concentrated oxygen in a pressurised chamber.)
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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