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Managing side effects

Radiotherapy is an effective treatment for many cancers but it can cause side effects. People react differently to radiotherapy and some people may have no side effects.

Side effects vary depending on the part of the body being treated. Reactions can also vary from one period of radiotherapy to 
the next. Before your treatment begins talk to your radiation oncologist about the possible side effects from your particular treatment. You will be asked to give your consent to having treatment so it’s useful to have all your questions answered.

There are ways to reduce discomfort and most side effects go away in time. Other less common side effects may be permanent and some may not start until treatment has finished.

During your course of treatment tell your radiation oncologist, radiation therapist or nurse of any side effects you notice. These can usually be controlled with the right care and medicine.

If you have severe side effects the doctor may change the treatment or prescribe a break in your course of treatment. However this may not be possible if your doctor thinks pausing the treatment could affect how well it’s working. Check with your doctor.

Always ask your radiation oncologist first before using any medicines, home remedies or creams to ease side effects. Some of these remedies can affect how radiotherapy works in your body.

During radiotherapy your body uses a lot of energy dealing with the effects of radiation on normal cells. Fatigue usually builds up slowly during the course of treatment particularly towards the end and may last for a few months after treatment finishes.

Many people find that they cannot do as much but others are able to continue their usual activities without much change.

  • Do fewer things and spread out daily activities.
  • Rest or take naps during the day if you can.
  • Let family and friends assist you. They can help with shopping, childcare, housework and driving.
  • Take a few weeks off work during or after your radiotherapy or reduce your hours. You may be able to work at home. Some people feel well enough to continue working full time and organise treatment appointments to suit their work hours.
  • Do light exercise such as walking, and keep up with your normal exercise routine. Research shows that regular exercise can boost energy levels and make you feel less tired. Talk to your health care team about suitable activities for you.
  • Limit caffeinated drinks like tea, coffee and soft drinks. While they may boost your energy, caffeine can make you feel jittery and irritable. It can also cause insomnia.
  • Eat a healthy, well-balanced diet and don’t skip meals.
  • Smoking reduces your energy. If you smoke talk to your doctor or call the Quitline on 13 7848 about stopping.
  • Skin problems – Radiotherapy may make your skin dry and itchy in the treatment area. Your skin may peel and look red, sunburnt or tanned. These reactions fade with time and you’ll be given special dressings. Some of the radiation passes through your body and out the other side so the skin in that part of your body may also be mildly affected.Ask your treatment staff before using any soap, deodorant, perfume, talcum powder, creams, cosmetics, medicines or other products on the treatment area. Many leave a coating that can interfere with radiotherapy. If needed you may be prescribed a special moisturiser.
  • Wear loose soft clothing such as cotton, next to your skin. Don’t wear tight-fitting clothes, girdles, close-fitting collars or belts over the treatment area.
  • Tell your doctor about changes to your skin e.g. cracks or blisters, moist areas, rashes, infections or peeling.
  • Choose loose, old clothes that you can throw out if the dye or ink marks rub off on them.
  • Stay out of the sun where possible, and cover your treated skin before going outside. Ask your doctor about using a sunscreen (SPF 30+).
  • Let the dye outlines wear off gradually.
  • Don’t put hot water bottles, heat packs, wheat bags or ice packs on the treatment area. Bathe or shower in lukewarm water – hot water can damage your sensitive skin. Pat skin dry with a soft towel.
  • Don’t use a razor blade on the treatment area. Check before using an electric razor.

Try to eat a healthy, balanced diet during treatment. Good nutrition helps you remain as well as possible and get the most from your treatment.

Some people lose interest in food during radiotherapy. This can depend on where on the body the radiotherapy is targeted. You may be advised to maintain adequate nutrition to complement how well radiotherapy is working.

  • Eat smaller amounts as often as possible.
  • Try to eat extra on days when you have an appetite.
  • Ask the hospital dietitian for advice on the best diet during treatment and recovery.
  • You may be advised to try a nutritional supplement. You can buy these at a pharmacy without a prescription and you can use them alone or with other foods.
  • Do not use any supplements or medicines without getting your treating doctor’s advice. Some supplements could interfere with treatment.
  • If you don’t feel like eating solid foods try enriching your drinks with powdered milk, yoghurt, eggs, honey or weight-gain supplements.
  • Sip water regularly to avoid becoming dehydrated.
  • Sometimes cooking smells can put you off eating. It may help if someone else prepares your food if possible or you could consider heating pre-cooked meals.
  • If you have radiotherapy to the head and neck area, chewing or swallowing might be difficult or painful. If eating is uncomfortable or difficult ask for something to relieve the pain. Good pain relief will help you eat well and feel better.

If you have hair in the area being treated (e.g. scalp, face or body) you may lose some or all of it during radiotherapy. Your hair will usually grow back a few months after the treatment has finished. Sometimes hair loss is permanent.

In general you will only lose hair in the treated area. However, when tumours on the face are treated hair on the back of the head may be lost due to small amounts of radiation passing through the head and out the other side.

  • Wear a wig, toupee, hat, scarf or turban. Do whatever feels comfortable and gives you the most confidence.
  • If you plan to wear a wig choose it early in your therapy so you can match it to the colour and style of your own hair. Cancer Council Helpline, your doctor or nurse may be able to help you find a wig.
    If you plan to leave your head bare protect it against sunburn and the cold.
  • Expect the hair that grows back to be different perhaps thinner or curly where it was once straight.
  • After a large dose of radiotherapy the new growth may be patchy for a while.
  • Ask your hairdresser to make your hair look as good as possible. In time your hair will probably return to its normal condition.
  • Contact Look Good…Feel Better. This program teaches techniques to help restore appearance and self-image during treatment. For more details see or call 1800 650 960.

If you have radiotherapy to your stomach area you may have an upset stomach.

These problems will usually get better when your treatment is over. Some people feel queasy for a few hours after external radiotherapy.

To help with nausea:

  • eat a bland snack such as toast, dry biscuits or apple juice before treatment
  • ask your doctor for medicine to prevent nausea
  • sip on fluids throughout the day to prevent dehydration
  • nibble dry biscuits.

Anti-nausea medication can help. This medicine can be taken before, during or after radiotherapy treatment. You may be given anti-nausea tablets to take at home. These are best taken regularly. It may take some time before you find an anti-nausea medication that works for you so let your nurse or doctor know early on if your symptoms aren’t being relieved. If you still feel nauseous after a few days or are vomiting for more than 24 hours contact your doctor. For more information, talk to your doctor or nurse or call 13 11 20 for information on eating well.

If you have radiotherapy to your stomach or part of your lower abdomen you may have diarrhoea. Diarrhoea can occur because the radiation irritates the lining of the bowel or stomach.

Symptoms include frequent loose, watery bowel movements, abdominal cramps and feeling an urgency to go to the toilet. It often begins in the third or fourth week of treatment.

  • Ask your treating doctor or nurse about what to expect and when to report diarrhoea.
  • Avoid high-fibre foods e.g. wholegrain bread and cereals and nuts and legumes, such as beans and lentils. You may also want to avoid spicy foods.
  • Drink lots of clear liquids as soon as diarrhoea starts, or when you feel it is going to start, to avoid becoming dehydrated. Apple juice, peach nectar, weak tea and clear broth will not worsen diarrhoea.
  • Ask your radiation oncologist to prescribe medicine to relieve diarrhoea.
  • After the diarrhoea has cleared up it is important to slowly reintroduce a healthy eating plan that includes fresh fruits and vegetables and wholegrain breads and pasta.
  • Check with your radiation oncologist, radiation therapist or nurse before taking any home remedies during your radiotherapy treatment. If you feel ill eat or drink as well as you can so your body gets the energy and nutrients it needs.
  • Contact your doctor immediately if you have blood in your faeces.

Radiotherapy is often used to treat cancer in the mouth, throat, neck or upper chest area. Depending on the area treated radiotherapy may affect your mouth and teeth and make eating and swallowing difficult.

After several weeks of treatment your mouth or throat may become dry and sore and your voice may become hoarse. This will gradually improve after treatment is completed but may take several weeks or even months depending on the treatment you’ve had. You may also have thick phlegm in your throat or a lump-like feeling that makes it hard to swallow.

Recovery of normal taste can sometimes take a long time after treatment is completed.

  • Suck ice chips and sip cool drinks to keep your mouth wet.
  • Avoid tobacco and alcohol because they will dry your mouth even more.
  • Try to have more liquids or soft food if chewing and swallowing are painful.
  • If your sense of taste changes during radiotherapy try different ways of preparing food. For example add lemon juice to meat and vegetables, marinate foods or add spices.
  • If eating is uncomfortable or difficult ask for something to relieve the pain. Good pain relief will help you eat well and feel better.
  • Ask your doctor or nurse for information about artificial saliva to moisten your mouth.

Radiotherapy to the mouth may increase the chance of tooth decay or other problems in the long-term. Future dental work can be more difficult due to problems with healing. It is often recommended that you have a dental check-up before treatment begins so that any dental work you need can be carried out prior to treatment.

Your dentist will give you detailed instructions about caring for your mouth and teeth to help prevent tooth decay and to deal with problems such as mouth sores. You will need ongoing dental care after treatment is completed.

Some cancer patients may be able to obtain dental services under Medicare. Visit or call Medicare on 13 20 11.

  • Rinse your mouth regularly with a non-alcoholic mouthwash recommended by your doctor or dentist.
  • Your doctor may also refer you to a dietitian who can suggest nourishing foods that will not hurt your mouth.
  • If you lose too much weight you may need extra feeding through a tube that goes into your stomach. Your doctor will discuss this with you.
  • See a speech pathologist if you have difficulty swallowing.