Side effects tend to start a few days after the radiotherapy begins. They gradually get worse during the treatment. They can continue to get worse after your treatment ends. But they usually begin to improve after 1 or 2 weeks.
Everyone is different and the side effects vary from person to person. You may not have all of the effects mentioned.
Side effects can include:
You are likely to feel very tired during your treatment. It tends to get worse as the treatment goes on. You might also feel weak and lack energy.
After a while you may need to sleep after each radiotherapy session. Rest when you need to.
Tiredness gets better once you finish treatment but it can carry on for some months.
Various things can help you to reduce tiredness and cope with it, for example exercise. Some research has shown that taking gentle exercise can give you more energy. It is important to balance exercise with resting.
Your mouth and throat might get sore. It may be painful to swallow drinks or food. You will have mouth washes to keep your mouth healthy.
You can have painkillers to reduce the soreness. Take them half an hour before meals to make eating easier.
During and after radiotherapy, you might have a feeling of a lump in the throat when you swallow. This can make it difficult to swallow solid foods.
This problem is often at its worst about 10 days to 2 weeks after you finish treatment.
Tips for eating and drinking
Drink about 3 litres of water a day while having treatment. Eating soft foods helps.
Make sure that you eat slowly and avoid eating late in the day. Drink plenty during and after meals to soften your food. And eat small amounts often rather than big meals.
Try different foods to find out which are easiest to swallow. You can have high calorie drinks to boost your calorie intake if you need them.
You might need to have liquid food into your vein or through a tube into your nose or stomach if you can’t eat enough.
Your hair may fall out in the treatment area.
Your voice might get husky or croaky and sound weaker. This can last for a while after your treatment.
You might be more likely to get mouth infections and tooth problems. You may need dental checkups more often. Fluoride mouthwashes twice a day can help to protect your teeth.
Remember to tell your dentist you have had radiotherapy to your mouth before you have any dental work. They may need to change your treatment. They might also need to talk to your radiotherapy doctor before giving you any treatment.
Your skin might go red or darker in the treatment area. You may also get redness or darkening on the other side of your body. This is where the radiotherapy beams leave the body.
The red or darker areas can also feel sore. Your radiographers will give you creams to soothe the skin. The soreness usually goes away within 2 to 4 weeks of ending the treatment.
Long term side effects
Most side effects gradually go away in the weeks or months after treatment. However some side effects can continue or might start some months or years later.
Side effects if you have chemotherapy with radiotherapy
Chemotherapy combined with radiotherapy can make some side effects worse. Combining these treatments is called chemoradiotherapy.