Side effects of radiotherapy and how to cope

The side effects of radiotherapy are related to the unwanted damage sustained by surrounding tissue.

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To minimise these unwanted effects, the total dose of radiation is split into up to 20 fractions given, for example, every weekday for 4 weeks. The dose of radiotherapy used to relieve symptoms such as bone pain is usually lower so you may have a shorter course of treatment and less chance of side effects.

Sore skin

Radiotherapy, like all treatments for pancreatic cancer comes with side effects. One of the most common is damage to the skin around the radiotherapy site. The skin can become sore and discoloured or itchy. This normally begins a few weeks into treatment and ends a few weeks afterwards.

Talk to your health care professional if your skin becomes uncomfortable. They may recommend washing and moisturising skin with unperfumed products and carefully patting dry the area affected. Wearing a high factor sunscreen will help prevent environmental damage to the skin. Wearing loose fitting clothing and avoiding wet shaving may also help to prevent further irritation.


Many people also find that they are affected fatigue when having radiotherapy. You may feel more tired and find it difficult to carry out everyday activities. Fatigue can continue for weeks or months after treatment. You may find that you need more help with some everyday tasks and want to get more rest. However, it is also important to get regular light exercise such as walking to help boost your energy levels.

Nausea and vomiting

Some people can feel and/or be sick during radiotherapy treatment, especially if it is in combination with chemotherapy. Especially if the area affected by the treatment is in the same area as the stomach such as the pancreas. Sickness can last for a few weeks after treatment has finished.

You may be prescribed medication to manage feeling or being sick. This could be tablet based or given through injection, patches or suppositories depending on what works best for you.

Tips for coping with sickness & nausea:

  • Eat little and often especially before treatment (e.g. soup and dry biscuits or toast), and drink as much fluid as possible.
  • Instead of drinking a lot at once, try sipping small amounts of liquid often. Sucking on ice cubes can also help to increase your fluid intake.
  • If you wake up feeling sick, eat a dry biscuit (ginger biscuits are supposed to help with nausea) or a slice of toast. This is better than skipping breakfast or forcing yourself to eat. If you are diabetic, consult your medical team.
  • Fizzy drinks such as ginger ale or soda water can often help relieve an upset stomach.
  • It is important to keep up your fluid intake to prevent you from becoming dehydrated if you have been vomiting a lot. You should contact your medical team if you are unable to keep fluids down.
  • Avoid strong odours and cooking smells, which can trigger nausea and vomiting.
  • Sometimes the taste of certain types of food can change. Your sense of taste should return to normal a few weeks after you have completed your treatment.
  • Speak to your dietician for more detailed advice on eating and drinking while undergoing radiotherapy treatment

Mouth sores

Some radiotherapy drugs can cause mouth sores such as ulcers or infections. If you notice any change in your mouth or throat, such as ulcers or thickened saliva, or if you find it difficult to swallow, contact your medical team.

If you have dental problems and need to see a dentist, speak to your doctor first. You should also tell your dentist that you are having radiotherapy.

Tips for dealing with mouth sores:

  • Use a soft toothbrush to clean your teeth.
  • Avoid mouthwashes that contain alcohol—a salt mouthwash may help
  • ulcers to heal.
  • Eat moist foods such as soup. Avoid foods that are very hot, spicy or
  • coarse.
  • Sucking on ice while you’re having intravenous (through a drip)
  • radiotherapy may help to reduce mouth ulcers.
  • Avoid smoking and alcohol as these can irritate your mouth.

Constipation or diarrhoea

Some radiotherapy drugs and pain relief medications can cause constipation or diarrhoea. Speak to a member of your medical team if your bowel habits change significantly.

Tips for dealing with constipation:

  • Tell your medical team if you have constipation for more than a couple of days. They may change your medication or give you treatment to relieve it.
  • Juices such as prune juice can sometimes help ease constipation.
  • Eating more high-fibre foods, such as wholegrain bread and pasta,
  • bran, fruit and vegetables, nuts and legumes (e.g. baked beans or lentils) may help.
  • Drink plenty of fluids.
  • Light exercise, such as walking, may help to get your bowels moving again.

Tips for dealing with diarrhoea:

  • Drink plenty of water to replace lost fluids.
  • Avoid spicy or rich food and food that is fatty or fried. Cutting out wholegrain foods and raw fruits and vegetables and replacing with bland food such as boiled rice may help.
  • Limit the amount of fruit juices, strong tea and coffee and alcohol you drink, as these can stimulate the bowel.
  • Speak to your pharmacist about any over-the-counter remedies that may be helpful in treating diarrhoea.
  • If the diarrhoea becomes severe, it can cause dehydration and you may need to be admitted to hospital to receive additional fluids via a drip.

Minimising the side effects

Depending on the reason you are having radiotherapy and the side affects you experience, your medical team may alter the dose of your medication. The radiation you are given will also be split into multiple treatment sessions of into up to 20 fractions given, for example, every weekday for 4 weeks. The dose of radiotherapy used to relieve symptoms such as bone pain is usually lower so you may have a shorter course of treatment and less chance of side effects. This regimen may be able to be adjusted if you struggle with side effects.