Side effects of radiotherapy

Side effects during treatment

Radiotherapy affects people in different ways, so it’s difficult to predict exactly how you will react. Some people have only mild side effects but for others the side effects are more severe. Some of the main side effects are explained below.

Tiredness and weakness

Most people feel tired while they are having radiotherapy, particularly if they are having treatment over several weeks. This is because the body is repairing the damage to healthy cells. Or tiredness can be due to low levels of red blood cells (anaemia). You might also feel weak and as though you don’t have the energy to do your normal daily activities. This may last for a few weeks after the treatment ends. Rest if you need to and try to exercise a little when you can. This can help to reduce the tiredness.

Sore skin

Some people get sore skin in the area being treated. The skin may look reddened or darker than usual. It may also get dry and itchy. The skin may break or small blisters can start to form in the area. The staff in the radiotherapy department can advise you on the best way of coping with this.

Loss of hair in the treatment area

Radiotherapy makes the hair fall out in the treatment area. Hair in other parts of the body is not affected. The hair should begin to grow back again a few weeks after the treatment ends.

Other side effects

Other side effects that you may have, depend on the area of the body being treated. Tell your doctor, nurse or radiographer about any side effects. They can help you find ways of reducing the effects and coping with them. They can give you leaflets which describe the side effects.

Possible long-term side effects

For many people the side effects of radiotherapy wear off within a few weeks of the treatment ending, and they can go back to a normal life. But for some people radiotherapy can cause long-term side effects.

The possibility of long-term side effects depends on the type of cancer and its size and position. It might also depend on how close the cancer is to nerves or other important organs or tissues.

It is important to ask your doctor, specialist nurse or radiographer about the possibility of long-term side effects. Depending on the position of the cancer, the possible long-term effects might include:

  • a change in skin colour in the treatment area
  • a dry mouth
  • breathing problems
  • loss of ability to become pregnant or father a child (infertility)
  • low sex drive
  • erection problems (impotence)
  • long-term soreness and pain
  • bowel changes
  • bladder inflammation

Long-term side effects

Sex and fertility Chemotherapy might affect your sex life. You could feel tired and lose interest in sex.
Some chemotherapy drugs can affect fertility. If you’re hoping to have a child, discuss it with your doctor before you start treatment. There might be steps that you and your doctor can take to help keep your fertility.
Feeling and being sick Sickness caused by chemotherapy can start within a couple of hours of starting your treatment and only last a day or so. Or it can come on more than 24 hours after the start of treatment. This is called delayed onset nausea and vomiting and usually lasts about a week.

Sometimes sickness doesn’t start until you have had your first few cycles of chemotherapy. It all depends on the chemotherapy drugs you have and how you react to them. This can vary from person to person.
If you are being sick with chemotherapy, do tell your doctor or chemotherapy nurse. There are lots of different anti sickness medicines and some work better for some people than others.

Hair, skin and nails Some chemotherapy drugs make some of your hair fall out, so that your hair is thinner.

Other chemotherapy drugs make all the hair on your head and body fall out, including eyebrows and eyelashes.

Losing your hair can be distressing. But it’s temporary and the hair starts to grow back a few weeks after treatment ends.

Some chemotherapy drugs can make your skin dry and sensitive. Some may cause rashes. You may find that your skin is more likely to burn in the sun or react to chemicals. So be careful when you’re in the sun, and wear at least factor 15 sun protection.

If you have dry skin, avoid swimming while you are having treatment. Some people find that their nails also change and become dry, ridged or brittle or have white lines on them.

Late side effects Most chemotherapy side effects are temporary and disappear once your treatment is over.
But for some people, chemotherapy can cause long-term changes in the body. Some of these changes may happen months or many years after the treatment has finished.

Late side effects can include early menopause, infertility, changes to feeling in your hands and feet (peripheral neuropathy) and heart and lung problems. Your doctor and chemo nurse can talk to you about the risk of late side effects with the drugs you’re having

Cancer Research UK is independent from the EAU and a source of trusted information for all.

© Cancer Research UK [2002] All right reserved. Information taken 23/02/2018.