Everyone is different and side effects can vary from person to person. You won't have all the side effects mentioned. Do talk to your healthcare team if you are worried about your side effects or have any questions.
Short term side effects
These can start during treatment and continue to get worse while you are having your treatment. They usually continue for about 2 to 4 weeks after your treatment has finished.
Tiredness and weakness
You might feel tired during your radiotherapy treatment. It tends to get worse as the treatment goes on. You might also feel weak and lack energy. Rest when you need to.
Tiredness can carry on for some weeks after the treatment has ended but it usually improves gradually.
Various things can help you to reduce tiredness and cope with it, such as exercise. Some research has shown that taking gentle exercise can give you more energy. It's important to balance exercise with resting.
Sometimes the skin feels tender or sensitive to touch. If this happens do let your
Your skin might go red or darker in the treatment area. You may also get redness or darkening of the skin on the other side of your body. This is where the radiotherapy beams leave the body. Your skin might always be slightly darker in that area.
Your skin can also feel sore. Your radiographer will give you creams to soothe the skin. The soreness usually goes away within 2 to 4 weeks of ending the treatment.
Towards the end of the radiotherapy, the skin might break down, especially under the breast. Your nurse will use special dressings to cover and protect the area. The area usually heals up over a couple of weeks.
Tell the radiotherapy staff if you notice any skin changes.
Swelling of the breast
Radiotherapy can make it more difficult for fluid to drain from the breast tissue. This can cause swelling of the breast or chest area. Doctors call this lymphoedema.
The swelling usually goes down a few weeks after the treatment ends. But tell your doctor or radiographers if it doesn’t. They can arrange for you to see a lymphoedema specialist. You might have a type of massage called manual lymphatic drainage.
Loss of hair in the armpit
Your hair might fall out in the area under the arm (armpit) on the treated side.
You might also lose hair anywhere within the treatment area.
This can happen about 10 days after your treatment starts. It may take weeks or months to grow back. For some people, it may never grow back.
Problems moving your arm and shoulder
Radiotherapy might make it harder to move your arm and shoulder. This can affect your activities and work. It usually improves when the treatment finishes. Your nurse or physiotherapist can give you exercises to help.
It’s important to continue the arm exercise you were shown after your surgery. This will make it easier for you to lift your arm to the correct position during radiotherapy. It can also help stop your arm and shoulder from becoming stiff.
Radiotherapy can cause many different side effects, such as tiredness. The side effects you get will depend on the area you're having treatment to, but there are some general side effects you might experience regardless of where your cancer is. This video is about the general side effects you might have.
On screen text: Tiredness and weakness
Martin (Radiographer): As the normal cells repair themselves from the treatment this can use a lot of the body's resources, causing tiredness.
David: After about four weeks, I started to get tired. The body was starting to weaken.
Laurel: I was tired, day and night. Getting up in the morning was like a chore. I couldn't talk for 5 minutes. I would just sleep and just sleep and just wake up and sleep again.
Martin (Radiographer): Listen to your body. Take rests if you need to. Try not to overdo things.
Laurel: Don't fight with yourself too much. Just like go at a pace and just work with your body. If you can't make it today, you can't make it today.
David: You've got to rest. You have to take the time to rest.
Mary: Just going for them small walks. They really do help you. And even if it is just walking around your house or just walking around the block.
Martin (Radiographer): Doing exercise can help with tiredness by helping you maintain energy levels.
Mary: Being outside, that's a big, massive thing as well because you're feeling the fatigue and I think getting outside, just getting a bit of fresh air that really, really did help me.
Martin (Radiographer): The tiredness you can expect to begin within the first few weeks of treatment. Once it reaches its peak, about two weeks after treatment it recovers quite quickly after that.
Mary: It's not forever. You're not going to be like this forever and I did have to tell myself that.
Laurel: Two months after treatment, I start to feel less tired and that was a way forward because things start to really improve.
On screen text:
- Rest and have short naps when you need to
- Drink plenty of water
- Eat a balanced diet
- Do some gentle exercise
- Get some fresh air
On screen text: Sore skin
Martin (Radiographer): The radiotherapy can cause soreness of the skin. This only affects the area that you are having treated. This usually starts to appear about two weeks after you start treatment. You may notice this becoming more red and may become more itchy and sore as treatment continues.
David: After about ten days I started to get red on the area that they were targeting and it just progressively got redder and redder.
Laurel: My skin was dry and at the back was just like this triangle shape thing where it was like, okay, I'm a woman of colour, but it was really, really black.
David: Wasn't too painful, it was sort of annoying, rather than painful.
Martin (Radiographer): After treatment’s finished, the skin will remain sore for up to two weeks, but then recovers quite quickly.
Laurel: I haven’t got no scarring now at all.
David: It was maybe three or four weeks and then all the blemishes disappeared front and back.
Martin (Radiographer): When you start treatment we would advise you to carry on with your normal skincare routine but as the side effects develop, then your team will advise you on which products you can use on the skin safely.
Laurel: When I'm washing myself I use a sponge and you're just literally as it were just squirt it down, you don't rub the skin at all because it's already damaged. Pat dry, don't rub.
David: I spoke to the hospital about it and it was them that recommended this cream to put on, just to alleviate the symptoms.
Martin (Radiographer): We'd recommend wearing loose clothing and keeping the treatment area covered up against the sun and wind.
Laurel: I had to change most of my wardrobe. I only wore cotton.
David: Wearing T-shirts, soft clothing, nothing that would rub.
Mary: It's important when you go outside to make sure that you do wear that headscarf, or you do wear a hat or whatever it is.
Laurel: I wouldn't go in the sun at all, at all because my skin was - I know it was too delicate.
On screen text:
- Don’t rub the area, press if it is itchy and dab your skin dry
- Don’t use perfume, perfumed soaps or lotions on the area
- Don’t shave the area
- Only use creams or dressings advised by your specialist or radiographer
- Wear loose fitting clothing
- Avoid strong sun or cold winds
- Make sure you wear sunscreen
On screen text: Hair loss
Martin (Radiographer): Radiotherapy can cause hair loss in the area that's being treated, whereas chemotherapy can cause hair loss all over the body.
Mary: 2 to 3 weeks after the radiotherapy, I was brushing my hair and loads came out on the brush. I knew it was going to happen, but it was just hard when it happened.
Martin (Radiographer): In most cases the hair will grow back. This can take a couple of months and the hair may have a slightly different colour or texture.
Mary: Mine did grow back and there's a lot of grey in it so I have to dye it. This is not my original colour. It's very slow growing back.
Martin (Radiographer): Use a simple soap to clean the area. Be gentle with the skin in that area and after washing pat the area dry with a soft towel.
On screen text:
- Radiotherapy can make hair fall out in the treatment area
- It won’t cause hair to fall out in other parts of your body
- Your hair might grow back a few weeks after treatment ends
- If your hair won’t grow back, then your doctor should tell you
- Don’t use perfume, perfumed soaps, or lotions on the area
On screen text: Your mental health
Laurel: I felt frustrated. Some days were really, really challenging where there were just tears without words.
Mary: It's a mixture of emotions. You feel angry and you feel frustrated. You lose your confidence.
Martin (Radiographer): Radiotherapy can cause a lot of emotions at various times during the treatment. You may feel sad or anxious or depressed, which is quite normal. It's good to talk to people about your experiences, whether that's your team at the hospital or friends and family.
David: I couldn't praise the team highly enough. Everybody that was involved were unbelievable and if it hadn't been for them, I just don't think I would have gotten through with it.
Mary: I did have a nurse as well and she had the experience of dealing with people that went through brain surgery, went through radiotherapy so it was just great that I could reach out.
Martin (Radiographer): Your team will be able to give you information about local patient support services that are available, that includes things like counselling and complementary therapies.
Laurel: A referral from the hospital counselling, which I attended for about a year.
Martin (Radiographer): There's also lots of support available online and in your local area.
Mary: I went on loads of different forums and I spoke to loads of different people and it really, really helped me. If I didn't do that, I don't think I would have got through most days.
Laurel: If you get a bit cranky or feel a bit low, go for it. But there's so much help out there and that's why I'm pushing forward like don't sit down in silence. It's the same thing, just get the help you need.
On screen text:
- There is help available – ask the hospital for support
- Talk to your friends and family about how you are feeling
- Ask about local support groups
- Your GP or hospital can provide counselling
- You can get help and support online through forums
If you're experiencing a side effect that hasn't been covered in this video, you can find more information on the Cancer Research UK website.
On screen text: For more information go to: cruk.org/radiotherapy/side-effects
Long term side effects
Most side effects gradually go away in the weeks or months after treatment. But some side effects can continue or might start some months or years later.
Most of these side effects are rare. You might get one or two of them. There are things you can do to deal with any side effects that you have.
A swollen arm
Some people get a swelling in the arm called lymphoedema after radiotherapy or surgery to the armpit. You can help to prevent this swelling and if it happens there are treatments to control it.
The treatment area might look permanently tanned after your treatment has finished. This is not harmful.
Later, you might appear to have very tiny broken veins in the skin called telangiectasia.
You can cover up any skin changes with camouflage make up. Your GP can prescribe it.
There are different colours for all skin tones. Some clinical nurse specialists are trained in showing you how to apply it.
Your consultant or GP can refer you to the skin camouflage service run by Changing Faces. This free service teaches you how to apply the make up and creams. It can also advise you on the best products to buy.
The British Association of Skin Camouflage can also help.
Changes in the shape, size, and feel of the breast
In time radiotherapy can cause the breast tissue to change shape or shrink in size a little. This can happen to your natural breast tissue or a reconstructed breast.
After radiotherapy, the breast might feel hard and less stretchy. This is due to a side effect called radiation fibrosis. This side effect is usually mild.
Sometimes the breast can shrink a little over time. This is because radiotherapy can make the breast tissue contract so that the breast gradually gets smaller.
An implant in a reconstructed breast can become hard (capsular contracture) and may need replacing.
Let your surgeon know of any changes, they may be able to do some minor surgical adjustments to improve the look.
A cough and breathlessness happen in some people who have radiotherapy to the chest area, but this is not common. The problems are due to changes in the lung tissue called chronic radiation pneumonitis. They might start many months or a few years after treatment.
Let your doctor know if you notice any changes in your breathing or if you cough up a lot of mucus.
You might have regular tests to check how well your lungs work. Treatment with steroids or other medicines can help you to breathe more easily.
Many years after radiotherapy to the left breast, some people might have changes to their heart. But this is rare.
Radiotherapy can make the bones in the treated area become weaker after many years. This can cause pain and can also increase the risk of fractures.
Your doctor or nurse can check your bone strength with a
Nerve damage around the treatment area
Scaring from radiotherapy may cause nerve damage in the arm on the treated side. This can develop many years after your treatment. Symptoms include tingling, numbness, pain, and weakness. In some people, it may cause some loss of movement in the arm and shoulder.
Speak to your doctor if you notice any of these symptoms.
Radiotherapy treatment may cause another type of cancer in many years’ time. These are rare, your doctor will talk to you about these risks.
If you have side effects
Let your doctor or nurse know if you have side effects or are worried about anything.
When treatment ends you usually have regular appointments for about 5 years afterwards. You can talk to your doctor or nurse at these appointments. But you don't have to wait for your next appointment if you get a new side effect or are worried about anything. You can bring the appointment forward.